Beta-amino ester gas hydrate inhibitors

ABSTRACT

Disclosed herein are beta-amino ester surfactant compounds and compositions useful in applications relating to inhibition of gas hydrate agglomerates in the production, transportation, storage, and separation of crude oil and natural gas. Also disclosed herein are methods of using the compounds and compositions as gas hydrate inhibitors, particularly in applications relating to the production, transportation, storage, and separation of crude oil and natural gas.

TECHNICAL FIELD

The present disclosure relates generally to low dosage hydrateinhibitors, and more particularly to beta-amino ester surfactants forthe inhibition of gas hydrate plugs.

BACKGROUND

Natural gas hydrates are ice-like solids that form when methane gas andwater are exposed to high pressures and low temperatures. Hydrates areformed when hydrogen-bonded water molecules organize into networks thatcan vary in size depending on the structure of the encapsulated guestmolecules. Gas hydrates can be easily formed during the transportationof oil and gas in pipelines when the appropriate conditions are present.If hydrates are not managed properly, they often result in lost oilproduction, pipeline damage, and safety hazards to field workers.

There are several methods to avoid hydrate blockages. These methodsinclude raising the temperature (e.g., insulation, and electric or waterheating), lowering the pressure, removing the water, and addinganti-freeze chemicals. These techniques are often very expensive anddifficult to manage. Perhaps the most common method of hydrateinhibition in the oil and gas industry is the addition of thermodynamicinhibitors (anti-freeze chemicals). These substances shift the hydrateformation temperature and therefore reduce the temperature at which thehydrates form at a given pressure and water content. Methanol andethylene glycol are among the most common thermodynamic inhibitors usedin the oil industry. Although thermodynamic inhibitors are quiteeffective, large doses are required to achieve high concentration in thewater phase. Thermodynamic inhibitors are regularly dosed atconcentrations as high as 50% based on water content during oil and gasproduction. Therefore, there is a substantial cost associated with thetransportation and storage of large quantities of these solvents.

A more cost-effective alternative is the use of low dosage hydrateinhibitors (LDHIs); as they generally require less that 2% dose toinhibit the nucleation, growth, or agglomeration of gas hydrates. Thereare two general types of LDHIs, kinetic hydrate inhibitors (KHIs) andanti-agglomerants (AAs). KHIs work by delaying the growth of gas hydratecrystals and as anti-nucleators. AAs allow the hydrates to form, butthey prevent them from agglomerating and accumulating into larger massescapable of causing plugs. An AA enables gas hydrates to form, but in theshape of fluid slurry dispersed in the liquid hydrocarbon phase. Ingeneral, the water cut should be below 50% otherwise the slurry becomestoo viscous to transport. As consequence, significant research effort isbeing dedicated to develop AAs capable of operating under higherwater-cuts, and there still exists a need for improved compounds,compositions and methods for preventing formation of gas hydrateagglomerates in the oil and gas industry.

SUMMARY

In one aspect, disclosed are beta-amino ester surfactant compoundshaving formula (I),

wherein

R¹ is alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, orheterocyclyl;

R² is hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, or heterocyclyl, orR² may be absent;

R³ is hydrogen or alkyl;

R⁴ is alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, orheterocyclyl;

Z^(a) is C(R⁵R⁶), O, S, or N(R⁷);

Z^(b) is C(R⁸R⁹), O, S, or)N(R¹⁰);

Z^(c) is C(R¹¹) or N;

Z^(d) is C(R¹²R¹³), O, S, or N(R¹⁴);

Z^(e) is C(R¹⁵R¹⁶), O, S, or N(R¹⁷);

R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, and R¹⁷ are eachindependently selected from the group consisting of hydrogen, alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, and heterocyclyl;

R^(a) is independently selected from, at each occurrence, the groupconsisting of hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkyl, and heterocyclyl;

R^(b) is independently selected from, at each occurrence, the groupconsisting of hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkyl, and heterocyclyl;

X⁻ is a counterion or X⁻ may be absent, provided that X⁻ is present whenR² is present and X⁻ is absent when R² is absent;

m is any one of an integer from 1 to 100; and

n is any one of an integer from 1 to 50;

wherein said alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, andheterocyclyl are each independently, at each occurrence, substituted orunsubstituted with a suitable substituent.

In certain embodiments, R¹ is unsubstituted C₁-C₂₂ alkyl orunsubstituted C₂—C₂₂ alkenyl; R² is absent; R³ is hydrogen orunsubstituted C₁-C₆ alkyl; R⁴ is unsubstituted C₁-C₆ alkyl; Z^(a) isC(R⁵R⁶); Z^(b) is C(R⁸R⁹); Z^(c) is N; Z^(d) is C(R¹²R¹³); Z^(e) isC(R¹⁵R¹⁶), R⁵, R⁶, R⁸, R⁹, R¹², R¹³, R¹⁵, and R¹⁶ are each independentlyselected from the group consisting of hydrogen and unsubstituted C₁-C₆alkyl; R^(a) is hydrogen at each occurrence; R^(b) is hydrogen at eachoccurrence; X⁻ is absent; m is any one of an integer from 1 to 20; and nis 2.

In certain embodiments, R¹ is unsubstituted C₁-C₂₂ alkyl orunsubstituted C₂—C₂₂ alkenyl; R² is unsubstituted C₁-C₁₀ alkyl; R³ ishydrogen or unsubstituted C₁-C₆ alkyl; R⁴ is unsubstituted C₁-C₆ alkyl;Z^(a) is C(R⁵R⁶); Z^(b) is C(R⁸R⁹); Z^(c) is N; Z^(d) is C(R¹²R¹³);Z^(e) is C(R¹⁵R¹⁶), R⁵, R⁶, R⁸, R⁹, R¹², R¹³, R¹⁵, and R¹⁶ are eachindependently selected from the group consisting of hydrogen andunsubstituted C₁-C₆ alkyl; R^(a) is hydrogen at each occurrence; R^(b)is hydrogen at each occurrence; X⁻ is bromide or chloride; m is any oneof an integer from 1 to 20; and n is 2.

In certain embodiments, R³ is hydrogen.

In certain embodiments, R⁵, R⁶, R⁸, R⁹, R¹², R¹³, R¹⁵, and R¹⁶ are eachindependently hydrogen.

In certain embodiments, m is 2, 4, 10, or 20.

In certain embodiments, R¹ is —C₁₂H₂₅, —C₁₈H₃₇, or —C₁₈H₃₅.

In certain embodiments, the compound of formula (I) has formula (V),

wherein R¹, R², X⁻, and m are as defined above.

In certain embodiments, R¹ is —(CH₂)₁₁CH₃, —(CH₂)₁₇CH₃, or—(CH₂)₈CH═CH(CH₂)₇CH₃; R² is —(CH₂)₃CH₃, —(CH₂)₅CH₃, or R² is absent;and X⁻ is bromide, or X⁻ is absent, provided that X⁻ is present when R²is present and X⁻ is absent when R² is absent. In certain embodiments, mis 2, 4, 10, or 20.

In certain embodiments, the compound of formula (I) is selected from thegroup consisting of:

3,6,9,12-tetraoxatetracosyl 3-(4-methylpiperazin-1-yl)propanoate;

1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide;

1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide;

(Z)-2-(2-(octadec-9-enyloxy)ethoxy)ethyl3-(4-methylpiperazin-1-yl)propanoate;

(Z)-1-butyl-1-methyl-4-(3-(2-(2-(octadec-9-enyloxy)ethoxy)ethoxy)-3-oxopropyl)piperazin-1-iumbromide;

(Z)-1-hexyl-1-methyl-4-(3-(2-(2-(octadec-9-enyloxy)ethoxy)ethoxy)-3-oxopropyl)piperazin-1-iumbromide;

3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracontyl3-(4-methylpiperazin-1-yl)propanoate;

1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacontyl)piperazin-1-iumbromide;

1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacontyl)piperazin-1-iumbromide;

3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacontyl3-(4-methylpiperazin-1-yl)propanoate;

1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacontyl)piperazin-1-iumbromide;

1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacontyl)piperazin-1-iumbromide;

(Z)-3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracont-39-enyl3-(4-methylpiperazin-1-yl)propanoate;

(Z)-1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacont-43-enyl)piperazin-1-iumbromide;

(Z)-1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacont-43-enyl)piperazin-1-iumbromide;

(Z)-3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacont-69-enyl3 -(4-methylpiperazin-1-yl)propanoate;

(Z)-1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacont-73-enyl)piperazin-1-iumbromide; and

(Z)-1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacont-73-enyl)piperazin-1-iumbromide.

In another aspect, disclosed are gas hydrate inhibitor compositions. Incertain embodiments, the composition comprises one or more compounds offormula (I). In certain embodiments, the composition comprises a mixtureof compounds of formula (I).

In certain embodiments, the composition comprises one or more additivesindependently selected from the group consisting of synergisticcompounds, asphaltene inhibitors, paraffin inhibitors, corrosioninhibitors, scale inhibitors, emulsifiers, water clarifiers,dispersants, emulsion breakers, hydrogen sulfide scavengers, gas hydrateinhibitors, biocides, pH modifiers, surfactants, and solvents.

In certain embodiments, the composition comprises at least one solvent.In certain embodiments, the solvent is isopropanol, methanol, ethanol,heavy aromatic naptha, toluene, ethylene glycol, ethylene glycolmonobutyl ether (EGMBE), diethylene glycol monoethyl ether, xylene,kerosene, diesel, isobutanol, heptane, or a combination thereof.

In another aspect, disclosed are methods of inhibiting the formation ofhydrate agglomerates in a fluid or gas, the methods comprising adding tothe fluid or gas an effective amount of a compound of formula (I). Thefluid may comprise water, gas, and optionally liquid hydrocarbon. Incertain embodiments, the fluid has a salinity of 1 to 20 w/w percenttotal dissolved solids (TDS). In certain embodiments, the fluid has awater cut from 1 to 65 v/v percent.

In certain embodiments, the method includes treating the fluid or gaswith an effective amount of a composition comprising one or morecompounds of formula (I). In certain embodiments, the compositionfurther comprises one or more additional components, each componentindependently selected from the group consisting of synergisticcompounds, asphaltene inhibitors, paraffin inhibitors, corrosioninhibitors, scale inhibitors, emulsifiers, water clarifiers,dispersants, emulsion breakers, hydrogen sulfide scavengers, gas hydrateinhibitors, biocides, pH modifiers, surfactants, and solvents. Incertain embodiments, the composition comprises at least one solvent. Incertain embodiments, the solvent is isopropanol, methanol, ethanol,heavy aromatic naptha, toluene, ethylene glycol, ethylene glycolmonobutyl ether (EGMBE), diethylene glycol monoethyl ether, xylene,kerosene, diesel, isobutanol, heptane, or a combination thereof, or acombination thereof.

In certain embodiments, the method includes applying a compound offormula (I), or composition comprising a compound of formula (I), to agas or liquid produced or used in the production, transportation,storage, and/or separation of crude oil and natural gas. In certainembodiments, the fluid or gas is contained in an oil or gas pipeline.

The compounds, compositions, methods and processes are further describedherein.

DETAILED DESCRIPTION

Disclosed herein are beta-amino ester surfactant compounds andcompositions, methods of using said compounds and compositions, andprocesses for their preparation. The compounds and compositions areparticularly useful for the inhibition of gas hydrate agglomerates incrude oil and natural gas based products and processes. It is believedthe surfactants disclosed herein present an optimal combination ofhydrophilic portions (e.g., substituted piperazine) and hydrophobicportions (e.g., ethoxylated fatty alkyl groups), that together providesuperior anti-agglomerate performance over available surfactants. Thecompounds and compositions can effectively inhibit the formation of gashydrate plugs in crude oil and natural gas based products and processes.

1. DEFINITION OF TERMS

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art. In case of conflict, the present document, includingdefinitions, will control. Preferred methods and materials are describedbelow, although methods and materials similar or equivalent to thosedescribed herein can be used in practice or testing of the presentinvention. All publications, patent applications, patents and otherreferences mentioned herein are incorporated by reference in theirentirety. The materials, methods, and examples disclosed herein areillustrative only and not intended to be limiting.

The terms “comprise(s),” “include(s),” “having,” “has,” “can,”“contain(s),” and variants thereof, as used herein, are intended to beopen-ended transitional phrases, terms, or words that do not precludethe possibility of additional acts or structures. The singular forms“a,” “and” and “the” include plural references unless the contextclearly dictates otherwise. The present disclosure also contemplatesother embodiments “comprising,” “consisting of” and “consistingessentially of,” the embodiments or elements presented herein, whetherexplicitly set forth or not.

The term “suitable substituent”, as used herein, is intended to mean achemically acceptable functional group, preferably a moiety that doesnot negate the activity of the inventive compounds. Such suitablesubstituents include, but are not limited to halo groups, perfluoroalkylgroups, perfluoroalkoxy groups, alkyl groups, alkenyl groups, alkynylgroups, hydroxy groups, oxo groups, mercapto groups, alkylthio groups,alkoxy groups, aryl or heteroaryl groups, aryloxy or heteroaryloxygroups, aralkyl or heteroaralkyl groups, aralkoxy or heteroaralkoxygroups, HO—(C═O)— groups, heterocylic groups, cycloalkyl groups, aminogroups, alkyl- and dialkylamino groups, carbamoyl groups, alkylcarbonylgroups, alkoxycarbonyl groups, alkylaminocarbonyl groups, dialkylaminocarbonyl groups, arylcarbonyl groups, aryloxycarbonyl groups,alkylsulfonyl groups, arylsulfonyl groups and the like. Those skilled inthe art will appreciate that many substituents can be substituted byadditional substituents.

The term “alkyl”, as used herein, refers to a linear or branchedhydrocarbon radical, preferably having 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28,39, 30, 31, or 32 carbons. Alkyl groups include, but are not limited to,methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, secondary-butyl,and tertiary-butyl. Alkyl groups may be unsubstituted or substituted byone or more suitable substituents, as defined above.

The term “alkylenyl” or “alkylene” as used herein, refers to a divalentgroup derived from a saturated, straight or branched hydrocarbon chainof from 1 to 32 carbon atoms. The term “C₁-C₆ alkylene” means thosealkylene or alkylenyl groups having from 1 to 6 carbon atoms.Representative examples of alkylenyl groups include, but are not limitedto, —CH₂—, —CH(CH₃)—, —CH(C₂H₅)—, —CH(CH(CH₃)(C₂H₅))—,—C(H)(CH₃)CH₂CH₂—, —C(CH₃)₂—, —CH₂CH₂—, —CH₂CH₂CH₂—, —CH₂CH₂CH₂CH₂—, and—CH₂CH(CH₃)CH₂—. Alkylenyl groups may be unsubstituted or substituted byone or more suitable substituents, as defined above.

The term “alkenyl”, as used herein, refers to a straight or branchedhydrocarbon radical, preferably having 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 39,30, 31, or 32 carbons, and having one or more carbon-carbon doublebonds. Alkenyl groups include, but are not limited to, ethenyl,1-propenyl, 2-propenyl (allyl), iso-propenyl, 2-methyl-1-propenyl,1-butenyl, and 2-butenyl. Alkenyl groups may be unsubstituted orsubstituted by one or more suitable substituents, as defined above.

The term “alkenylenyl” or “alkenylene”, as used herein, refers to adivalent group derived from a straight or branched chain hydrocarbon of2 to 32 carbon atoms, which contains at least one carbon-carbon doublebond. Representative examples of alkenylenyl groups include, but are notlimited to, —C(H)═C(H) —C(H)═C(H)—CH₂—, —C(H)═C(H)—CH₂—CH₂—,—CH₂—C(H)═C(H)—CH₂—, —C(H)═C(H)—CH(CH₃)—, and—CH₂—C(H)═C(H)—CH(CH₂CH₃)—. Alkenylenyl groups may be unsubstituted orsubstituted by one or more suitable substituents, as defined above.

The term “alkynyl”, as used herein, refers to a straight or branchedhydrocarbon radical, preferably having 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 39,30, 31, or 32 carbons, and having one or more carbon-carbon triplebonds. Alkynyl groups include, but are not limited to, ethynyl,propynyl, and butynyl. Alkynyl groups may be unsubstituted orsubstituted by one or more suitable substituents, as defined above.

The term “alkynylenyl” or “alkynylene”, as used herein, refers to adivalent unsaturated hydrocarbon group which may be linear or branchedand which has at least one carbon-carbon triple bond. Representativeexamples of alkynylenyl groups include, but are not limited to, —C≡C—,—C≡C—CH₂—, —C≡C—CH₂—CH₂—, —CH₂—C≡C—CH₂—, —C≡C—CH(CH₃)—, and—CH₂—C≡C—CH(CH₂CH₃)—. Alkynylenyl groups may be unsubstituted orsubstituted by one or more suitable substituents, as defined above.

The term “alkoxy”, as used herein, refers to an alkyl group, as definedherein, appended to the parent molecular moiety through an oxygen atom.

The term “aryl”, as used herein, means monocyclic, bicyclic, ortricyclic aromatic radicals such as phenyl, naphthyl,tetrahydronaphthyl, indanyl and the like; optionally substituted by oneor more suitable substituents, preferably 1 to 5 suitable substituents,as defined above.

The term “carbonyl”, “(C═O)”, or “—C(O)—” (as used in phrases such asalkylcarbonyl, alkyl —(C═O) or alkoxycarbonyl) refers to the joinder ofthe >C═O moiety to a second moiety such as an alkyl or amino group (i.e.an amido group). Alkoxycarbonylamino (i.e. alkoxy(C═O)NH) refers to analkyl carbamate group. The carbonyl group is also equivalently definedherein as (C═O). Alkylcarbonylamino refers to groups such as acetamide.

The term “cycloalkyl”, as used herein, refers to a mono, bicyclic ortricyclic carbocyclic radical (e.g., cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl,cyclopentenyl, cyclohexenyl, bicyclo[2.2.1]heptanyl,bicyclo[3.2.1]octanyl and bicyclo[5.2.0]nonanyl, etc.); optionallycontaining 1 or 2 double bonds. Cycloalkyl groups may be unsubstitutedor substituted by one or more suitable substituents, preferably 1 to 5suitable substituents, as defined above.

The term “halo” or “halogen”, as used herein, refers to a fluoro,chloro, bromo or iodo radical.

The term “heteroaryl”, as used herein, refers to a monocyclic, bicyclic,or tricyclic aromatic heterocyclic group containing one or moreheteroatoms selected from O, S and N in the ring(s). Heteroaryl groupsinclude, but are not limited to, pyridyl, pyrazinyl, pyrimidinyl,pyridazinyl, thienyl, furyl, imidazolyl, pyrrolyl, oxazolyl (e.g.,1,3-oxazolyl, 1,2-oxazolyl), thiazolyl (e.g., 1,2-thiazolyl,1,3-thiazolyl), pyrazolyl, tetrazolyl, triazolyl (e.g., 1,2,3-triazolyl,1,2,4-triazolyl), oxadiazolyl (e.g., 1,2,3-oxadiazolyl), thiadiazolyl(e.g., 1,3,4-thiadiazolyl), quinolyl, isoquinolyl, benzothienyl,benzofuryl, and indolyl. Heteroaryl groups may be unsubstituted orsubstituted by one or more suitable substituents, preferably 1 to 5suitable substituents, as defined above.

The term “heterocycle” or “heterocyclyl”, as used herein, refers to amonocyclic, bicyclic, or tricyclic group containing 1 to 4 heteroatomsselected from N, O, S(O)_(n), NH or NR^(x), wherein R^(x) is a suitablesubstituent. Heterocyclic groups optionally contain 1 or 2 double bonds.Heterocyclic groups include, but are not limited to, azetidinyl,tetrahydrofuranyl, imidazolidinyl, pyrrolidinyl, piperidinyl,piperazinyl, oxazolidinyl, thiazolidinyl, pyrazolidinyl,thiomorpholinyl, tetrahydrothiazinyl, tetrahydro-thiadiazinyl,morpholinyl, oxetanyl, tetrahydrodiazinyl, oxazinyl, oxathiazinyl,indolinyl, isoindolinyl, quinuclidinyl, chromanyl, isochromanyl, andbenzoxazinyl. Examples of monocyclic saturated or partially saturatedring systems are tetrahydrofuran-2-yl, tetrahydrofuran-3-yl,imidazolidin-1-yl, imidazolidin-2-yl, imidazolidin-4-yl,pyrrolidin-1-yl, pyrrolidin-2-yl, pyrrolidin-3-yl, piperidin-1-yl,piperidin-2-yl, piperidin-3-yl, piperazin-1-yl, piperazin-2-yl,piperazin-3-yl, 1,3-oxazolidin-3-yl, isothiazolidine,1,3-thiazolidin-3-yl, 1,2-pyrazolidin-2-yl, 1,3-pyrazolidin-1-yl,thiomorpholin-yl, 1,2-tetrahydrothiazin-2-yl,1,3-tetrahydrothiazin-3-yl, tetrahydrothiadiazin-yl, morpholin-yl,1,2-tetrahydrodiazin-2-yl, 1,3-tetrahydrodiazin-1-yl, 1,4-oxazin-2-yl,and 1,2,5-oxathiazin-4-yl. Heterocyclic groups may be unsubstituted orsubstituted by one or more suitable substituents, preferably 1 to 3suitable substituents, as defined above.

The term “hydroxy”, as used herein, refers to an —OH group.

The term “oxo”, as used herein, refers to a double bonded oxygen (═O)radical wherein the bond partner is a carbon atom. Such a radical canalso be thought as a carbonyl group.

The term “cocoamine”, as used herein, may refer to a mixture of aminescomprising about 95% primary amines, and about 5% combined secondary andtertiary amines. The primary amines are about 6% hexylamine (C₆), about7% decylamine (C₁₀), about 51% dodecylamine (C₁₂), about 19%tetradecylamine (C₁₄), about 9% hexadecylamine (C₁₆), about 2%octadecylamine (C₁₈), and about 6% combined content of octadecenylamine(C₁₈) and octadecadienylamine (C₁₈). The major component of cocoamine isC₁₂H₂₅NH₂. Cocoamine is sold under the product name ARMEEN® C by AkzoNobel Surface Chemistry, LLC, 15200 Almeda Road, Houston, Tex. 77053,United States of America.

The term “coco”, as used herein, may refes to a mixture of carbon chainradicals derived from cocoamine. The mixture of carbon chain radicals isabout 6% hexyl (C₆), about 7% decyl (C₁₀), about 51% dodecyl (C₁₂),about 19% tetradecyl (C₁₄), about 9% hexadecyl (C₁₆), about 2% octadecyl(C₁₈), and about 6% combined content of octadecenyl (C₁₈) andoctadecadienyl (C₁₈). The major component of coco is a —C₁₂H₂₅ carbonchain radical.

The term “counterion”, as used herein, means a halide (e.g., fluoride,chloride, bromide, iodide), a carboxylate anion, such as selected fromdeprotonation of mineral acid, acrylic acid, acetic acid, methacrylicacid, glycolic acid, thioglycolic acid, propionic acid, butyric acid,and the like, or any other suitable anionic species.

The term “water cut”, as used herein, means the percentage of water in acomposition containing an oil and water mixture.

2. COMPOUNDS

Compounds of the invention include beta-amino ester surfactantcompounds. The compounds may be particularly useful in the oil and gasindustry for the inhibition of gas hydrate agglomerates.

In one aspect, compounds of the invention have formula (I),

wherein

R¹ is alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, orheterocyclyl;

R² is hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, or heterocyclyl, orR² may be absent;

R³ is hydrogen or alkyl;

R⁴ is alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, orheterocyclyl;

Z^(a) is C(R⁵R⁶), O, S, or N(R⁷);

Z^(b) is C(R⁸R⁹), O, S, or N(R¹⁹);

Z^(c) is C(R¹¹) or N;

Z^(d) is C(R¹²R¹³), O, S, or N(R¹⁴);

Z^(e) is C(R¹⁵R¹⁶), O, S, or N(R¹⁷);

R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, and R¹⁷ are eachindependently selected from the group consisting of hydrogen, alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, and heterocyclyl;

R^(a) is independently selected from, at each occurrence, the groupconsisting of hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkyl, and heterocyclyl;

R^(b) is independently selected from, at each occurrence, the groupconsisting of hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkyl, and heterocyclyl;

X⁻ is a counterion or X⁻ may be absent, provided that X⁻ is present whenR² is present and X⁻ is absent when R² is absent;

m is any one of an integer from 1 to 100; and

n is any one of an integer from 1 to 50;

wherein said alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, andheterocyclyl are each independently, at each occurrence, substituted orunsubstituted with a suitable substituent.

It is to be understood that when R² is absent, the correspondingnitrogen atom in the heterocyclic ring of formula (I) lacks the depictedpositive charge.

In certain embodiments, R¹ is substituted or unsubstituted alkyl. Incertain embodiments, R¹ is substituted or unsubstituted straight chainalkyl. In certain embodiments, R¹ is substituted or unsubstitutedbranched alkyl. In certain embodiments, R¹ is substituted orunsubstituted C₁-C₃₂ alkyl, substituted or unsubstituted C₁-C₂₂ alkyl,substituted or unsubstituted C₁-C₁₆ alkyl, substituted or unsubstitutedC₁-C₁₀ alkyl, or substituted or unsubstituted C₁-C₆ alkyl. In certainembodiments, R¹ is substituted or unsubstituted straight chain C₁-C₂₂alkyl. In certain embodiments, R¹ is substituted or unsubstitutedbranched C₁-C₂₂ alkyl.

In certain embodiments, R¹ is —CH₃, —C₂H₅, —C₃H₇, —C₄H₉, —C₅H₁₁, —C₆H₁₃,—C₇H₁₅, —C₉H₁₉, —C₁₀-C₂₁, —C₁₁H₂₃, —C₁₂H₂₅, —C₁₃H₂₇, —C₁₄H₂₉, —C₁₅H₃₁,—C₁₆H₃₃, —C₁₇H₃₅, —C₁₈H₃₇, —C₁₉H₃₉, —C₂₀H₄₁, —C₂₁H₄₃, —C₂₂H₄₅, —C₂₃H₄₇,—C₂₄H₄₉, —C₂₅H₅₁, —C₂₆H₅₃, —C₂₇H₅₅, —C₂₈H₅₇, —C₂₉H₅₉, —C₃₉H₆₁, —C₃₁H₆₃,or —C₃₂H₆₅. In certain embodiments, R¹ is —C₁₂H₂₅. In certainembodiments, R¹ is —C₁₈H₃₇.

In certain embodiments, R¹ is —CH₃, —CH₂CH₃, —(CH₂)₂CH₃, —(CH₂)₃CH₃,—(CH₂)₄CH₃, —(CH₂)₅CH₃, —(CH₂)₆CH₃, —(CH₂)₇CH₃, —(CH₂)₈CH₃, —(CH₂)₉CH₃,—(CH₂)₁₀CH₃, —(CH₂)₁₁CH₃, —(CH₂)₁₂CH₃, —(CH₂)₁₃CH₃, —(CH₂)₁₄CH₃,—(CH₂)₁₅CH₃, —(CH₂)₁₆CH₃, —(CH₂)₁₇CH₃, —(CH₂)₁₈C¹¹ ₃, —(CH₂)₁₉CH₃,—(CH₂)_(2o)CH₃, —(CH₂)₂₁CH₃, —(CH₂)₂₂CH₃, —(CH₂)₂₃CH₃, —(CH₂)₂₄CH₃,—(CH₂)₂₅CH₃, —(CH₂)₂₆CH₃, —(CH₂)₂₇CH₃, —(CH₂)₂₈CH₃, —(CH₂)₂₉CH₃,—(CH₂)₃or —CH₃, —(CH₂)₃₁CH₃, or —(CH₂)₃₂CH₃. In certain embodiments, R¹is —(CH₂)₁₁CH₃. In certain embodiments, R¹ is —(CH₂)₁₇CH₃.

In certain embodiments, R¹ is substituted or unsubstituted alkenyl. Incertain embodiments, R¹ is substituted or unsubstituted straight chainalkenyl. In certain embodiments, R¹ is substituted or unsubstitutedbranched alkenyl. In certain embodiments, R¹ is substituted orunsubstituted C₂-C₃₂ alkenyl, substituted or unsubstituted C₂-C₂₂alkenyl, substituted or unsubstituted C₂-C₁₆ alkenyl, substituted orunsubstituted C₂-C₁₀ alkenyl, or substituted or unsubstituted C₂-C₆alkenyl. In certain embodiments, R¹ is substituted or unsubstitutedC₃-C₃₂ alkenyl, substituted or unsubstituted C₃-C₂₂ alkenyl, substitutedor unsubstituted C₃-C₁₆ alkenyl, or substituted or unsubstituted C₁₂-C₁₈alkenyl. In certain embodiments, R¹ is substituted or unsubstitutedstraight chain C₂-C₂₂ alkenyl. In certain embodiments, is substituted orunsubstituted branched C₂-C₂₂ alkenyl.

In certain embodiments, R¹ is —C₃H₅, —C₄H₇, —C₅H₉, —C₆H₁₁, —C₇H₁₃,—C₈H₁₅, —C₉H₁₇, —C₁₁H₂₁, —C₁₂H₂₃, —C₁₃H₂₅, —C₁₄H₂₇, —C₁₅H₂₉, —C₁₆H₃₁,—C₁₇H₃₃, —C₁₈H₃₅, —C₁₉H₃₇, —C₂₀H₃₉, —C₂₁H₄₁, —C₂₂H₄₃, —C₂₃H₄₅, —C₂₄H₄₇,—C₂₅H₄₉, —C₂₆H₅₁, —C₂₇H₅₃, —C₂₈H₅₅, —C₂₉H₅₇, —C₃₀H₅₉, —C₃₁H₆₁, or—C₃₂H₆₃. In certain embodiments, R¹ is —C₁₈H₃₅.

In certain embodiments, R¹ is —C₅H₇, —C₆H₉, —C₈H₁₃, —C₉H₁₅, —C₁₀H₁₇,—C₁₁H₁₉, —C₁₂H₂₁, —C₁₃H₂₃, —C₁₄H₂₅, —C₁₅H₂₇, —C₁₆H₂₉, —C₁₇H₃₁, —C₁₈H₃₃,—C₁₉H₃₅, —C₂₀H₃₇, —C₂₁H₃₉, —C₂₂H₄₁, —C₂₃H₄₃, —C₂₄H₄₅, —C₂₅H₄₇, —C₂₆H₄₉,—C₂₇H₅₁, —C₂₈H₅₃, —C₂₉H₅₅, —C₃₀H₅₇, —C₃₁H₅₉, or —C₃₂H₆₁.

In certain embodiments, R¹ is —C₇H₉, —C₁₀H₁₅, —C₁₁H₁₇, —C₁₂H₁₉, —C₁₃H₂₁,—C₁₄H₂₃, —C₁₅H₂₅, —C₁₆H₂₇, —C₁₇H₂₉, —C₁₈11₃₁, —C₁₉H₃₃, —C₂₀H₃₅, —C₂₁H₃₇,—C₂₂H₃₉, —C₂₃H₄₁, —C₂₄H₄₃, —C₂₅H₄₅, —C₂₆H₄₇, —C₂₇H₄₉, —C₂₈H₅₁, —C₂₉H₅₃,—C₃₀H₅₅, —C₃₁H₅₇, or —C₃₂H₅₉.

In certain embodiments, R¹ is —C₉H₁₁, —C₁₀H₁₃, —C₁₁H₁₅, —C₁₂H₁₇,—C₁₃H₁₉, —C₁₄H₂₁, —C₁₅H₂₃, —C₁₆H₂₅, —C₁₇H₂₇, —C₁₈11₂₉, —C₁₉H₃₁, —C₂₀H₃₃,—C₂₁H₃₅, —C₂₂H₃₇, —C₂₃H₃₉, —C₂₄H₄₁, —C₂₅H₄₃, —C₂₆H₄₅, —C₂₇H₄₇, —C₂₈H₄₉,—C₂₉H₅₁, —C₃₀H₅₃, —C₃₁H₅₅, or —C₃₂H₅₇.

In certain embodiments, R¹ is —C₁₁H₁₃, —C₁₂H₁₅, —C₁₃H₁₇, —C₁₄H₁₉,—C₁₅H₂₁, —C₁₆H₂₃, —C₁₇H₂₅, —C₁₈H₂₇, —C₁₉H₂₉, —C₂₀H₃₁, —C₂₁H₃₃, —C₂₂H₃₅,—C₂₃H₃₇, —C₂₄H₃₉, —C₂₅H₄₁, —C₂₆H₄₃, —C₂₇H₄₅, —C₂₈H₄₇, —C₂₉H₄₉, —C₃₀H₅₁,—C₃₁H₅₃, or —C₃₂H₅₅.

In certain embodiments, R¹ is —C₁₃H₁₅, —C₁₄H₁₇, —C₁₅H₁₉, —C₁₆H₂₁,—C₁₇H₂₃, —C₁₈H₂₅, —C₁₉H₂₇, —C₂₀H₂₉, —C₂₁H₃₁, —C₂₂H₃₃, —C₂₃H₃₅, —C₂₄H₃₇,—C₂₅H₃₉, —C₂₆H₄₁, —C₂₇H₄₃, —C₂₈H₄₅, —C₂₉H₄₇, —C₃₀H₄₉, —C₃₁H₅₁, or—C₃₂H₅₃.

In certain embodiments, R¹ is—(CH₂)₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃,—(CH₂)₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃,—(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₇CH₃,—(CH₂)₃CH═CHCH₂CH₂CH═CHCH₂CH═CH(CH₂)₄CH₃,—(CH₂)₃CH═CH(CH₂)₄CH═CHCH₂CH═CH(CH₂)₄CH₃,—(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃,—(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃,—(CH₂)₃CH═CHCH═CHCH═CHCH═CHCH═CH(CH₂)₄CH₃, —(CH₂)₄CH═CH(CH₂)₈CH₃,—(CH₂)₄CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃,—(CH₂)₄CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃,—(CH₂)₄CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃,—(CH₂)₄CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃,—(CH₂)₄CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂ CH₃,—(CH₂)₅CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃,—(CH₂)₅CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃,—(CH₂)₅CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃,—(CH2)6CH═CHCH═CHCH═CH(CH₂)₄CH₃,—(CH₂)₆CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CH(CH₂)₃CH₃,—(CH₂)₇CH═CH(CH₂)₅CH₃, —(CH₂)₇CH═CH(CH₂)₇CH₃,—(CH₂)₇CH═CHCH═CHCH═CH(CH₂)₃CH₃, —(CH₂)₇CH═CHCH═CH(CH₂)₅CH₃,—(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃,—(CH₂)₇CH═CHCH═CHCH₂CH₂CH═CHCH₂CH₃, —(CH₂)₇CH═CHCH═CHCH═CHCH═CHCH₂CH₃,—(CH₂)₇CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃,—(CH₂)₇CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃,—(CH₂)₇CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃,—(CH₂)₈CH═CH(CH₂)₇CH₃, —(CH₂)₉CH═CH(CH₂)₅CH₃,—(CH₂)₉CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₉CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃,—(CH₂)₉CH═CH(CH₂)₇CH₃, —(CH₂)₁₁CH═CH(CH₂)₅CH₃, —(CH₂)₁₁CH═CH(CH₂)₇CH₃,—(CH₂)₁₁CH═CHCH₂CH═CH(CH₂)₄CH₃, or —(CH₂)₁₃CH═CH(CH₂)₇CH₃.

In certain embodiments, R¹ is (Z)-tetradec-9-enyl, (Z)-hexadec-9-enyl,(Z)-hexadec-6-enyl, (Z)-octadec-9-enyl, (E)-octadec-9-enyl,(E)-octadec-11-enyl, (9Z,12Z)-octadeca-9,12-dienyl,(9E,12E)-octadeca-9,12-dienyl, (9Z,12Z,15Z)-octadeca-9,12,15-trienyl,(5Z,8Z,11Z,14Z)-icosa-5,8,11,14-tetraenyl,(5Z,8Z,11Z,14Z,17Z)-icosa-5,8,11,14,17-pentaenyl, (Z)-docos-13-enyl,(4Z,7Z,10Z,13Z,16Z,19Z)-docosa-4,7,10,13,16,19-hexaenyl,(7Z,10Z,13Z)-hexadeca-7,10,13-trienyl,(6Z,9Z,12Z,15Z)-octadeca-6,9,12,15-tetraenyl,(11Z,14Z,17Z)-icosa-11,14,17-trienyl,(5Z,8Z,11Z,14Z,17Z)-icosa-5,8,11,14,17-pentaenyl,(6Z,9Z,12Z,15Z,18Z)-henicosa-6,9,12,15,18-pentaenyl,(7Z,10Z,13Z,16Z,19Z)-docosa-7,10,13,16,19-pentaenyl,(4Z,7Z,10Z,13Z,16Z)-docosa-4,7,10,13,16-pentaenyl,(9Z,12Z,15Z,18Z,21Z)-tetracosa-9,12,15,18,21-pentaenyl,(6Z,9Z,12Z,15Z,18Z,21Z)-tetracosa-6,9,12,15,18,21-hexaenyl,(6Z,9Z,12Z)-octadeca-6,9,12-trienyl, (11Z,14Z)-icosa-11,14-dienyl,(8Z,11Z,14Z)-icosa-8,11,14-trienyl, (13Z,16Z)-docosa-13,16-dienyl,(7Z,10Z,13Z,16Z)-docosa-7,10,13,16-tetraenyl,(9Z,12Z,15Z,18Z)-tetracosa-9,12,15,18-tetraenyl,(6Z,9Z,12Z,15Z,18Z)-tetracosa-6,9,12,15,18-pentaenyl, (Z)-eicos-11-enyl,(Z)-icos-13-enyl, (5Z,8Z,11Z)-eicosa-5,8,11-trienyl,(Z)-tetracos-15-enyl, (9Z,11E)-octadeca-9,11-dienyl,(8E,10E,12Z)-octadeca-8,10,12-trienyl,(8E,10E,12E)-octadeca-8,10,12-trienyl,(8E,10Z,12E)-octadeca-8,10,12-trienyl,(9Z,11E,13E)-octadeca-9,11,13-trienyl,(9E,11E,13E)-octadeca-9,11,13-trienyl,(9E,11E,13Z)-octadeca-9,11,13-trienyl,(9Z,11E,13Z)-octadeca-9,11,13-trienyl,(9E,11Z,15E)-octadeca-9,11,15-trienyl,(9Z,11E,13E,15Z)-octadeca-9,11,13,15-tetraenyl,(9E,11E,13E,15E)-octadeca-9,11,13,15-tetraenyl,(5Z,8Z,10E,12E,14Z)-icosa-5,8,10,12,14-pentaenyl,(5Z,9Z,12Z)-octadeca-5,9,12-trienyl, or(5Z,11Z,14Z)-icosa-5,11,14-trienyl. In certain embodiments, R¹ is(Z)-octadec-9-enyl.

In certain embodiments, R¹ is substituted or unsubstituted alkynyl. Incertain embodiments, R¹ is substituted or unsubstituted straight chainalkynyl. In certain embodiments, R¹ is substituted or unsubstitutedbranched alkynyl. In certain embodiments, R¹ is substituted orunsubstituted C₂-C₃₂ alkynyl, substituted or unsubstituted C₂-C₂₂alkynyl, substituted or unsubstituted C₂-C₁₆ alkynyl, substituted orunsubstituted C₂-C₁₀ alkynyl, or substituted or unsubstituted C₂-C₆alkynyl. In certain embodiments, R¹ is substituted or unsubstitutedstraight chain C₂-C₂₂ alkynyl. In certain embodiments, R¹ is substitutedor unsubstituted branched C₂-C₂₂ alkynyl.

In certain embodiments, R¹ is substituted or unsubstituted aryl. Incertain embodiments, R¹ is substituted or unsubstituted phenyl. Incertain embodiments, R¹ is 4-octylphenyl. In certain embodiments, R¹ is4-nonylphenyl. In certain embodiments, R¹ is 2,4,6-tri-tertbutylphenyl.

In certain embodiments, —(OCH₂CHR³)_(m)OR¹ of formula (I), and thus R¹,is derived from a fatty alcohol of formula: HO(CH₂CHR³O)_(m)R¹, whereinR¹, R³, and m are as defined herein. In certain embodiments, the fattyalcohol is an ethoxylated fatty alcohol or a propoxylated fatty alcohol.In certain embodiments, —(OCH₂CHR³)_(m)OR¹ of formula (I) is derivedfrom HO(CH₂CH₂O)₄C₁₂H₂₅ sold under the tradename Brij™ L4 by SigmaAldrich, St. Louis, Mo. In certain embodiments, —(OCH₂CHR³)_(m)OR¹ offormula (I) is derived from HO(CH₂CH₂O)₂₀C₁₆H₃₃ sold under the tradenameBrij™ 58 by Sigma Aldrich. In certain embodiments, —(OCH₂CHR³)_(m)OR¹ offormula (I) is derived from HO(CH₂CH₂O)_(m)C₁₈H₃₅, wherein m˜20, soldunder the tradename Brij™ 98 by Sigma Aldrich. In certain embodiments,—(OCH₂CHR³)_(m)OR¹ of formula (I) is derived from HO(CH₂CH₂O)_(m)C₁₆H₃₃,wherein m˜2, sold under the tradename Brij™ 52 by Sigma Aldrich. Incertain embodiments, —(OCH₂CHR³)_(m)OR¹ of formula (I) is derived fromHO(CH₂CH₂O)_(m)C₁₈H₃₇, wherein m˜100, sold under the tradename Brij™ S100 by Sigma Aldrich. In certain embodiments, —(OCH₂CHR³)_(m)OR¹ offormula (I) is derived from HO(CH₂CH₂O)₂₃C₁₂H₂₅, sold under thetradename Brij™ L23 by Sigma Aldrich. In certain embodiments,—(OCH₂CHR³)_(m)OR¹ of formula (I) is derived from HO(CH₂CH₂O)_(m)C₁₈H₃₅,wherein m˜2, sold under the tradename Brij™ 93 by Sigma Aldrich. Incertain embodiments, —(OCH₂CHR³)_(m)OR¹ of formula (I) is derived fromHO(CH₂CH₂O)_(m)C₁₆H₃₃, wherein m˜10, sold under the tradename Brij™ C10by Sigma Aldrich. In certain embodiments, —(OCH₂CHR³)_(m)OR¹ of formula(I) is derived from HO(CH₂CH₂O)_(m)C₁₈H₃₅, wherein m˜10, sold under thetradename Brij™ C10 by Sigma Aldrich. In certain embodiments,—(OCH₂CHR³)_(m)OR¹ of formula (I) is derived from HO(CH₂CH₂O)_(m)C₁₈H₃₇,wherein m˜10, sold under the tradename Brij™ S10 by Sigma Aldrich. Incertain embodiments, —(OCH₂CHR³)_(m)OR¹ of formula (I) is derived fromHO(CH₂CH₂O)_(m)C₁₈H₃₇, wherein m˜20, sold under the tradename Brij™0 S20by Sigma Aldrich. In certain embodiments, —(OCH₂CHR³)_(m)OR¹ of formula(I) is derived from HO(CH₂CH₂O)₂C₁₈H₃₇, sold under the tradename Brij™S2 by Sigma Aldrich.

In certain embodiments, —(OCH₂CHR³)_(m)OR¹ of formula (I) is derivedfrom HO(CH₂CH(CH₃)O)₁₀C₁₆H₃₃, sold under the tradename Procetyl™ 10 byCroda Chemicals Europe, East Yorkshire, England. In certain embodiments,—(OCH₂CHR³)_(m)OR¹ of formula (I) is derived fromHO(CH₂CH(CH₃)O)₁₅C₁₈H₃₇, sold under the tradename Prostearyl™ 15 byCroda Chemicals Europe.

In certain embodiments, R² is hydrogen.

In certain embodiments, R² is substituted or unsubstituted alkyl. Incertain embodiments, R² is substituted or unsubstituted straight chainalkyl. In certain embodiments, R² is substituted or unsubstitutedbranched alkyl. In certain embodiments, R² is substituted orunsubstituted C₁-C₁₀ alkyl, or substituted or unsubstituted C₁-C₆ alkyl.

In certain embodiments, R² is —CH₃, —C₂H₅, —C₃H₇, —C₄H₉, —C₅H₁₁, —C₆H₁₃,—C₇H₁₅, —C₈H₁₇, —C₉H₁₉, or —C₁₀H₂₁. In certain embodiments, R² is —C₄H₉.In certain embodiments, R² is —C₆H₁₃. In certain embodiments, R² is—CH₃, —CH₂CH₃, —(CH₂)₂CH₃, —(CH₂)₃CH₃, —(CH₂)₄CH₃, —(CH₂)₅CH₃,—(CH₂)₆CH₃, —(CH₂)₇CH₃, —(CH₂)₈CH₃, or —(CH₂)₉CH₃. In certainembodiments, R² is —(CH₂)₃CH₃. In certain embodiments, R² is —(CH₂)₅CH₃.

In certain embodiments, R² is —CH₂-aryl, wherein aryl is substituted orunsubstituted. In certain embodiments, R² is unsubstituted benzyl (i.e.,—CH₂C₆H₅).

In certain embodiments, R² is substituted or unsubstituted alkenyl. Incertain embodiments, R² is substituted or unsubstituted straight chainalkenyl. In certain embodiments, R² is substituted or unsubstitutedbranched alkenyl. In certain embodiments, R² is substituted orunsubstituted C₂-C₁₀ alkenyl, or substituted or unsubstituted C₂-C₆alkenyl. In certain embodiments, R² is substituted or unsubstitutedC₃-C₁₀ alkenyl, or substituted or unsubstituted C₃-C₆ alkenyl.

In certain embodiments, R² is —C₃H₅, —C₄H₇, —C₅H₉, —C₇H₁₃, —C₈H₁₅,—C₉H₁₇, or —C₁₀H₁₉. In certain embodiments, R² is —C₅H₇, —C₆H₉, —C₈H₁₃,—C₉H₁₅, or —C₁₀H₁₇. In certain embodiments, R² is —C₇H₉, —C₈H₁₁, —C₉H₁₃,or —C₁₀H₁₅. In certain embodiments, R² is —C₉H₁₁, or —C₁₀H₁₃.

In certain embodiments, R² is substituted or unsubstituted alkynyl. Incertain embodiments, R² is substituted or unsubstituted straight chainalkynyl. In certain embodiments, R² is substituted or unsubstitutedbranched alkynyl. In certain embodiments, R² is substituted orunsubstituted C₂—C₁₀ alkynyl, or substituted or unsubstituted C₂-C₆alkynyl. In certain embodiments, R² is substituted or unsubstitutedC₃-C₁₀ alkynyl, or substituted or unsubstituted C₃-C₆ alkynyl. Incertain embodiments, R² is —CH₂C≡CH, —CH₂C≡CCH₃, —CH₂C≡CCH₂CH₃,—CH₂CH₂C≡CH, —CH₂CH₂C≡CCH₃, or —CH₂CH₂C≡CCH₂CH₃.

In certain embodiments, R² is absent.

In certain embodiments R³ is hydrogen.

In certain embodiments, R³ is substituted or unsubstituted alkyl. Incertain embodiments, R³ is substituted or unsubstituted straight chainalkyl. In certain embodiments, R³ is substituted or unsubstitutedbranched alkyl. In certain embodiments, R³ is substituted orunsubstituted C₁-C₁₀ alkyl, or substituted or unsubstituted C₁-C₆ alkyl.

In certain embodiments, R³ is —CH₃, —C₂H₅, —C₃H₇, —C₄H₉, —C₅H₁₁, —C₆H₁₃,—C₇H₁₅, —C₈H₁₇, —C₉H₁₉, or —C₁₀H₂₁. In certain embodiments, R³ is —CH₃,—CH₂CH₃, —(CH₂)₂CH₃, —(CH₂)₃CH₃, —(CH₂)₄CH₃, —(CH₂)₅CH₃, —(CH₂)₆CH₃,—(CH₂)₇CH₃, —(CH₂)₈CH₃, or —(CH₂)₉CH₃ In certain embodiments, R³ ismethyl (—CH₃).

In certain embodiments, R⁴ is substituted or unsubstituted alkyl. Incertain embodiments, R⁴ is substituted or unsubstituted straight chainalkyl. In certain embodiments, R⁴ is substituted or unsubstitutedbranched alkyl. In certain embodiments, R⁴ is substituted orunsubstituted C₁-C₁₀ alkyl, or substituted or unsubstituted C₁-C₆ alkyl.

In certain embodiments, R⁴ is —CH₃, —C₂H₅, —C₃H₇, —C₄H₉, —C₅H₁₁, —C₆H₁₃,—C₇H₁₅, —C₈H₁₇, —C₉H₁₉, or —C₁₀H₂₁. In certain embodiments, R⁴ is —CH₃,—CH₂CH₃, —(CH₂)₂CH₃, —(CH₂)₃CH₃, —(CH₂)₄CH₃, —(CH₂)₅CH₃, —(CH₂)₆CH₃,—(CH₂)₇CH₃, —(CH₂)₈CH₃, or —(CH₂)₉CH₃ In certain embodiments, R⁴ ismethyl (—CH₃).

In certain embodiments, R⁴ is substituted or unsubstituted alkenyl. Incertain embodiments, R⁴ is substituted or unsubstituted straight chainalkenyl. In certain embodiments, R⁴ is substituted or unsubstitutedbranched alkenyl. In certain embodiments, R⁴ is substituted orunsubstituted C₂-C₁₀ alkenyl, substituted or unsubstituted C₂-C₆alkenyl, or substituted or unsubstituted C₃-C₆ alkenyl.

In certain embodiments, R⁴ is —C₃H₅, —C₄H₇, —C₅H₉, —C₆H₁₁, —C₇H₁₃,—C₈H₁₅, —C₉H₁₇, or —C₁₀H₁₉. In certain embodiments, R⁴ is —C₅H₇, —C₆H₉,—C₇H₁₁, —C₈H₁₃, —C₉H₁₅, or —C₁₀H₁₇. In certain embodiments, R⁴ is —C₇H₉,—C₈H₁₁, —C₉H₁₃, or —C₁₀H₁₅. In certain embodiments, R⁴ is —C₉H₁₁, or—C₁₀H₁₃.

In certain embodiments, R⁴ is substituted or unsubstituted alkynyl. Incertain embodiments, R⁴ is substituted or unsubstituted straight chainalkynyl. In certain embodiments, R⁴ is substituted or unsubstitutedbranched alkynyl. In certain embodiments, R⁴ is substituted orunsubstituted C₂-C₁₀ alkynyl, substituted or unsubstituted C₂-C₆alkynyl, or substituted or unsubstituted C₃-C₆ alkynyl. In certainembodiments, R⁴ is —CH₂C≡CH, —CH₂C≡CCH₃, —CH₂C≡CCH₂CH₃, —CH₂CH₂C≡CH,—CH₂CH₂C≡CCH₃, or —CH₂CH₂C≡CCH₂CH₃.

In certain embodiments, Z^(a) is C(R⁵R⁶) or N(R⁷); Z^(b) is C(R⁸R⁹)or)N(R¹⁰); Z^(c) is N; Z^(d) is C(R¹²R¹³) or N(R¹⁴); and Z^(e) isC(R¹⁵R¹⁶) or N(R¹⁷). In certain embodiments, Z^(a) is C(R⁵R⁶); Z^(b) isC(R⁸R⁹); Z^(c) is N; Z^(d) is C(R¹²R¹³); and Z^(e) is C(R¹⁵ R¹⁶). Incertain embodiments, Z^(a) is C(R⁵R⁶); Z^(b) is C(R⁸R⁹); Z^(c) isC(R¹¹), Z^(d) is C(R¹²R¹³); and Z^(e) is C(R¹⁵R¹⁶).

In certain embodiments, Z^(a) is C(R⁵R⁶), Z^(b) is C(R⁸R⁹); Z^(c) is N;Z^(d) is C(R¹²R¹³), Z^(e) is C(R¹⁵R¹⁶), and R⁵, R⁶, R⁸, R⁹, R¹², R¹³,R¹⁵, and R¹⁶ are each independently selected from the group consistingof hydrogen, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, six-memberedaryl, five- or six-membered heteroaryl, C₃-C₈ cycloalkyl, and five- orsix-membered heterocyclyl. In certain embodiments, Z^(a) is C(R⁵R⁶),Z^(b) is C(R⁸R⁹); Z^(c) is N; Z^(d) is C(R¹²R¹³); Z^(e) is C(R¹⁵R¹⁶);and R⁵, R⁶, R⁸, R⁹, R¹², R¹³, R¹⁵, and R¹⁶ are each independentlyselected from the group consisting of hydrogen and C₁-C₆ alkyl. Incertain embodiments, Z^(a) is C(R⁵R⁶), Z^(b) is C(R⁸R⁹); Z^(c) is N;Z^(d) is C(R¹²R¹³); Z^(e) is C(R¹⁵R¹⁶); and R⁵, R⁶, R⁸, R⁹, R¹², R¹³,R¹⁵, and R¹⁶ are each hydrogen.

In certain embodiments, R^(a) and R^(b) are each independently selectedfrom, at each occurrence, the group consisting of hydrogen, C₁-C₆ alkyl,C₂-C₆ alkenyl, C₂-C₆ alkynyl, six-membered aryl, five- or six-memberedheteroaryl, C₃-C₈ cycloalkyl, and five- or six-membered heterocyclyl. Incertain embodiments, R^(a) and R^(b) are each independently selectedfrom, at each occurrence, the group consisting of hydrogen and C₁-C₆alkyl. In certain embodiments, R^(a) and R^(b) are each hydrogen.

In certain embodiments, X⁻ is fluoride, chloride, bromide, iodide, orcarboxylate anion, such as selected from deprotonation of mineral acid,acrylic acid, acetic acid, methacrylic acid, glycolic acid, thioglycolicacid, propionic acid, or butyric acid. In certain embodiments, X⁻ ischloride or bromide. In certain embodiments, X⁻ is bromide.

In certain embodiments, m is any one of an integer from 1 to 30 (i.e., mis 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30). In certain embodiments,m is any one of an integer from 1 to 20 (i.e., m is 1, 2, 3, 4, 5, 6, 7,8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20). In certainembodiments, m is 2, 4, 10, or 20. In certain embodiments, m is 2. Incertain embodiments, m is 4. In certain embodiments, m is 10. In certainembodiments, m is 20.

In certain embodiments, n is any one of an integer from 1 to 30 (i.e., nis 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30). In certain embodiments,n is any one of an integer from 1 to 10 (i.e., n is 1, 2, 3, 4, 5, 6, 7,8, 9, or 10). In certain embodiments, n is 2.

In another aspect, compounds of the invention have formula (II),

wherein

In one preferred embodiment, R¹ is alkyl, alkenyl, or alkynyl; R² ishydrogen, alkyl, or benzyl, or R² is absent; R³ is alkyl or hydrogen; R⁴is alkyl; each R^(a) is independently hydrogen or alkyl; each R^(b) isindependently hydrogen or alkyl; X⁻ is a counterion or X⁻ is absent; andm is any one of an integer from 1 to 20. In another preferredembodiment, R¹ is C₁-C₂₂ alkyl, or C₁-C₂₂ alkenyl; R² is C₁-C₆ alkyl, orR² is absent; R³ is methyl or hydrogen; R⁴ is C₁-C₆ alkyl; each R^(a) isindependently hydrogen or C₁-C₆ alkyl; each R^(b) is independentlyhydrogen or C₁-C₆ alkyl; X⁻ is bromide or chloride, or X⁻ is absent; andm is any one of an integer from 1 to 20. In another preferredembodiment, R¹ is —C₁₂H₂₅, —C₁₈H₃₅, or —C₁₈H₃₇; R² is —C₄H₉ or —C₆H₁₃,or R² is absent; R³ is H or —CH₃; R⁴ is —CH₃; each R^(a) is hydrogen;each R^(b) is hydrogen; X⁻ is bromide or X⁻ is absent; and m is 2, 4,10, or 20. It is to be understood that when R² is absent, then X⁻ isabsent; and when R² is present, X⁻ is present. It is also to beunderstood that when R² is absent, the corresponding nitrogen atom inthe piperazine ring of formula (II) lacks the depicted positive charge.

In another aspect, compounds of the invention have formula (III),

wherein

R¹, R², R³, R⁴, X⁻, and m are as defined above.

In one preferred embodiment, R¹ is alkyl, alkenyl, or alkynyl; R² ishydrogen, alkyl, or benzyl, or R² is absent; R³ is alkyl or hydrogen; R⁴is alkyl; X⁻ is a counterion or X⁻ is absent; and m is any one of aninteger from 1 to 20. In another preferred embodiment, R¹ is C₁-C₂₂alkyl, or C₁-C₂₂ alkenyl; R² is C₁-C₆ alkyl, or R² is absent; R³ ismethyl or hydrogen; R⁴ is C₁-C₆ alkyl; X⁻ is bromide or chloride, or X⁻is absent; and m is any one of an integer from 1 to 20. In anotherpreferred embodiment, R¹ is —C₁₂H₂₅, —C₁₈F1₃₅, or —C₁₈H₃₇; R² is —C₄H₉or —C₆14₁₃, or R² is absent; R³ is H or —CH₃; R⁴ is —CH₃; X⁻ is bromideor X⁻ is absent; and m is 2, 4, 10, or 20. It is to be understood thatwhen R² is absent, then X⁻ is absent; and when R² is present, X⁻ ispresent. It is also to be understood that when R² is absent, thecorresponding nitrogen atom in the piperazine ring of formula (III)lacks the depicted positive charge.

In another aspect, compounds of the invention have formula (IV),

wherein

R¹, R², R³, X⁻, and m are as defined above.

In one preferred embodiment, R¹ is alkyl, alkenyl, or alkynyl; R² ishydrogen, alkyl, or benzyl, or R² is absent; R³ is alkyl or hydrogen; X⁻is a counterion or X⁻ is absent; and m is any one of an integer from 1to 20. In another preferred embodiment, R¹ is C₁-C₂₂ alkyl, or C₁-C₂₂alkenyl; R² is C₁-C₆ alkyl, or R² is absent; R³ is methyl or hydrogen;X⁻ is bromide or chloride, or X⁻ is absent; and m is any one of aninteger from 1 to 20. In another preferred embodiment, R¹ is —C₁₂H₂₅,—C₁₈H₃₅, or —C₁₈H₃₇; R² is —C₄H₉ or —C₆H₁₃, or R² is absent; R³ is H ormethyl; X⁻ is bromide or X⁻ is absent; and m is 2, 4, 10, or 20. It isto be understood that when R² is absent, then X⁻ is absent; and when R²is present, X⁻ is present. It is also to be understood that when R² isabsent, the corresponding nitrogen atom in the piperazine ring offormula (IV) lacks the depicted positive charge.

In another aspect, compounds of the invention have formula (V),

wherein

R¹ R², X⁻, and m are as defined above.

In one preferred embodiment, R¹ is alkyl, alkenyl, or alkynyl; R² ishydrogen, alkyl, or benzyl, or R² is absent; X⁻ is a counterion or X⁻ isabsent; and m is any one of an integer from 1 to 20. In anotherpreferred embodiment, R¹ is alkyl, alkenyl, or alkynyl; R² is hydrogen,alkyl, or benzyl; X⁻ is a counterion; and m is any one of an integerfrom 1 to 20. In another preferred embodiment, R¹ is C₁-C₂₂ alkyl, orC₁-C₂₂ alkenyl; R² is C₁-C₆ alkyl; X⁻ is bromide or chloride; and m isany one of an integer from 1 to 20. In another preferred embodiment, R¹is —C₁₂H₂₅, —C₁₈H₃₅, or —C₁₈H₃₇; R² is —C₄H₉ or —C₆14₁₃; X⁻ is bromide;and m is 2, 4, 10, or 20. It is to be understood that when R² is absent,then X⁻ is absent; and when R² is present, X⁻ is present. It is also tobe understood that when R² is absent, the corresponding nitrogen atom inthe piperazine ring of formula (V) lacks the depicted positive charge.

In another aspect, compounds of the invention have formula (VI),

wherein

R¹, R³, R⁴, and m are as defined above.

In one preferred embodiment, R¹ is alkyl, alkenyl, or alkynyl; R³ isalkyl or hydrogen; R⁴ is alkyl; and m is any one of an integer from 1 to20. In another preferred embodiment, R¹ is C₁-C₂₂ alkyl, or C₁-C₂₂alkenyl; R³ is methyl or hydrogen; R⁴ is C₁-C₆ alkyl; and m is any oneof an integer from 1 to 20. In another preferred embodiment, R¹ is—C₁₂H₂₅, —C₁₈H₃₅, or —C₁₈14₃₇; R³ is H or methyl; R⁴ is methyl; and m is2, 4, 10, or 20.

In another aspect, compounds of the invention have formula (VII),wherein

wherein

R¹ and m are as defined above.

In one preferred embodiment, R¹ is alkyl, alkenyl, or alkynyl; and m isany one of an integer from 1 to 20. In another preferred embodiment, R¹is C₁-C₂₂ alkyl, or C₁-C₂₂ alkenyl; and m is any one of an integer from1 to 20. In another preferred embodiment, R¹ is —C₁₂H₂₅, —C₁₈H₃₅, or—C₁₈14₃₇; and m is 2, 4, 10, or 20.

In another aspect, compounds of the invention have formula (VIII),wherein

wherein

R² is C₁-C₂₂ alkyl.

In one preferred embodiment, R² is unsubstituted C₁-C₂₂ alkyl. Inanother preferred embodiment, R² is unsubstituted straight chain C₁-C₂₂alkyl. In another preferred embodiment, R² is unsubstituted C₁-C₁₀alkyl. In another preferred embodiment, R² is unsubstituted straightchain C₁-C₁₀ alkyl. In another preferred embodiment, R² is unsubstitutedC₁-C₆ alkyl. In another preferred embodiment, R² is unsubstitutedstraight chain C₁-C₆ alkyl. In another preferred embodiment, R² isunsubstituted straight chain C₄—C₆ alkyl. In another preferredembodiment, R² is —CH₃, —C₂H₅, —C₃H₇, —C₄H₉, —C₅H₁₁, —C₆1⁻1₁₃, —C₇H₁₅,—C₈H₁₇, —C₉H₁₉, or —C₁₀H₂₁. In another preferred embodiment, R² is—C₄H₉. In another preferred embodiment, R² is —C₆H₁₃. In anotherpreferred embodiment, R² is —CH₃, —CH₂CH₃, —(CH₂)₂CH₃, —(CH₂)₃CH₃,—(CH₂)₄CH₃, —(CH₂)₅CH₃, —(CH₂)₆CH₃, —(CH₂)₇CH₃, —(CH₂)₈CH₃, or—(CH₂)₉CH₃. In another preferred embodiment, R² is —(CH₂)₃CH₃. Inanother preferred embodiment, R² is —(CH₂)₅CH₃.

In another aspect, compounds of the invention have formula (IX), wherein

wherein

R² is C₅-C₂₂ alkyl.

In one preferred embodiment, R² is unsubstituted C₅—C₂₂ alkyl. Inanother preferred embodiment, R² is unsubstituted straight chain C₅-C₂₂alkyl. In another preferred embodiment, R² is unsubstituted C₅-C₁₀alkyl. In another preferred embodiment, R² is unsubstituted straightchain C₅-C₁₀ alkyl. In another preferred embodiment, R² is unsubstitutedC₅-C₈ alkyl. In another preferred embodiment, R² is unsubstitutedstraight chain C₅-C₈ alkyl. In another preferred embodiment, R² isunsubstituted straight chain C₅-C₇ alkyl. In another preferredembodiment, R² is —C₅H₁₁, —C₆H₁₃, —C₇H₁₅, —C₈H₁₇, —C₉H₁₉, or —C₁₀H₂₁. Inanother preferred embodiment, R² is —C₆14₁₃. In another preferredembodiment, R² is —(CH₂)₄CH₃, —(CH₂)₅CH₃, —(CH₂)₆CH₃, —(CH₂)₇CH₃,—(CH₂)₈CH₃, or —(CH₂)₉CH₃. In another preferred embodiment, R² is—(CH₂)₅CH₃.

Exemplary compounds of the invention having formula (I) include, but arenot limited to:

3,6,9,12-tetraoxatetracosyl 3-(4-methylpiperazin-1-yl)propanoate;

1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide;

1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide;

(Z)-2-(2-(octadec-9-enyloxy)ethoxy)ethyl3-(4-methylpiperazin-1-yl)propanoate;

(Z)-1-butyl-1-methyl-4-(3-(2-(2-(octadec-9-enyloxy)ethoxy)ethoxy)-3-oxopropyl)piperazin-1-iumbromide;

(Z)-1-hexyl-1-methyl-4-(3-(2-(2-(octadec-9-enyloxy)ethoxy)ethoxy)-3-oxopropyl)piperazin-1-iumbromide;

3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracontyl3-(4-methylpiperazin-1-yl)propanoate;

1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacontyl)piperazin-1-iumbromide;

1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacontyl)piperazin-1-iumbromide;

3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacontyl3-(4-methylpiperazin-1-yl)propanoate;

1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacontyppiperazin-1-iumbromide;

1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacontyppiperazin-1-iumbromide;

(Z)-3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracont-39-enyl3-(4-methylpiperazin-1-yl)propanoate;

(Z)-1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacont-43-enyl)piperazin-1-iumbromide;

(Z)-1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacont-43-enyl)piperazin-1-iumbromide;

(Z)-3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacont-69-enyl3-(4-methylpiperazin-1-yl)propanoate;

(Z)-1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacont-73-enyOpiperazin-1-iumbromide; and

(Z)-1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacont-73-enyl)piperazin-1-iumbromide.

The compounds of the invention may contain asymmetric centers and canthus occur as racemates and racemic mixtures, single enantiomers,diastereomeric mixtures and individual diastereomers. Additionalasymmetric centers may be present depending upon the nature of thevarious substituents on the molecule. Each such asymmetric center willindependently produce two optical isomers and it is intended that all ofthe possible optical isomers and diastereomers in mixtures and as pureor partially purified compounds are included within the scope of thisinvention. The present invention is meant to comprehend all suchisomeric forms of these compounds.

3. COMPOSITIONS

The compositions disclosed herein include at least one compound asdescribed above. In certain embodiments, a composition of the inventioncontains a pure composition of a compound of formula (I). In otherembodiments, a composition of the invention contains a mixture of two ormore structurally distinct compounds of formula (I). In certainembodiments, a composition of the invention may comprise a mixture ofcompounds of formula (I), wherein one or more of R¹, R², R³, R⁴, Z^(a),Z^(b), Z^(c), Z^(d), Z^(e), R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹², R^(D), R¹⁴,R¹⁵, R¹⁶, R¹⁷, R^(a), R^(b), X⁻, m, and n are variable.

In certain embodiments, a composition of the invention contains amixture of compounds of formula (I) wherein R², R³, R⁴, Z^(a), Z^(b),Z^(c), Z^(d), Z^(e), R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵,R¹⁶, R¹⁷, R^(a), R^(b), X⁻, m, and n are the same across the compoundsof formula (I) in the composition, and R¹ is optionally variable acrossthe compounds of formula (I) in the composition. In certain embodiments,a composition of the invention contains a mixture of compounds offormula (I) wherein R¹, R², R³, R⁴, Z^(a), Z^(b), Z^(c), Z^(d), Z^(e),R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R^(a),R^(b), X⁻, and n are the same across the compounds of formula (I) in thecomposition, and m is optionally variable across the compounds offormula (I) in the composition. In certain embodiments, a composition ofthe invention contains a mixture of compounds of formula (I) wherein R²,R³, R⁴, Z^(a), Z^(b), Z^(c), Z^(d), Z^(e), R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹,R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R^(a), R^(b), X⁻, and n are the sameacross the compounds of formula (I) in the composition, and R¹ and m areoptionally variable across the compounds of formula (I) in thecomposition.

In certain embodiments, a composition of the invention contains a purecomposition of a compound of formula (II), a pure composition of acompound of formula (III), a pure composition of a compound of formula(IV), a pure composition of a compound of formula (V), a purecomposition of a compound of formula (VI), a pure composition of acompound of formula (VII), a pure composition of a compound of formula(VIII), a pure composition of a compound of formula (IX), or anycombination thereof, wherein the variables of said formulas are asdefined above.

In certain embodiments, a composition of the invention contains amixture of compounds of formula (II), a mixture of compounds of formula(III), a mixture of compounds of formula (IV), a mixture of compounds offormula (V), a mixture of compounds of formula (VI), a mixture ofcompounds of formula (VII), a mixture of compounds of formula (VIII), amixture of compounds of formula (IX), or any combination thereof,wherein the variables of said formulas are as defined above.

In certain embodiments, a composition of the invention comprises fromabout 1 to about 100 percent by weight of one or more compounds of theinvention. In certain embodiments, a composition of the invention is aneat composition of one or more compounds of the invention.

The compositions of the invention can optionally include one or moreadditives. Suitable additives include, but are not limited to,synergistic compounds, asphaltene inhibitors, paraffin inhibitors,corrosion inhibitors, scale inhibitors, emulsifiers, water clarifiers,dispersants, emulsion breakers, hydrogen sulfide scavengers, gas hydrateinhibitors, biocides, pH modifiers, surfactants, and solvents.

a. Synergistic Compounds

Suitable synergistic compounds include compounds that enhance the gashydrate inhibiting performance of the composition. In certainembodiments, the synergist compound(s) may be added to a fluid or gassimultaneously with a compound or composition of the invention, or maybe added separately from a compound or composition. In certainembodiments, the synergistic compound(s) may be preblended with acompound or composition of the invention before being added to a fluidor gas to be treated.

b. Asphaltene Inhibitors

Suitable asphaltene inhibitors include, but are not limited to,aliphatic sulphonic acids; alkyl aryl sulphonic acids; aryl sulfonates;lignosulfonates; alkylphenol/aldehyde resins and similar sulfonatedresins; polyolefin esters; polyolefin imides; polyolefin esters withalkyl, alkylenephenyl or alkylenepyridyl functional groups; polyolefinamides; polyolefin amides with alkyl, alkylenephenyl or alkylenepyridylfunctional groups; polyolefin imides with alkyl, alkylenephenyl oralkylenepyridyl functional groups; alkenyl/vinyl pyrrolidone copolymers;graft polymers of polyolefins with maleic anhydride or vinyl imidazole;hyperbranched polyester amides; polyalkoxylated asphaltenes, amphotericfatty acids, salts of alkyl succinates, sorbitan monooleate, andpolyisobutylene succinic anhydride.

c. Paraffin Inhibitors

Suitable paraffin inhibitors include, but are not limited to, paraffincrystal modifiers, and dispersant/crystal modifier combinations.Suitable paraffin crystal modifiers include, but are not limited to,alkyl acrylate copolymers, alkyl acrylate vinylpyridine copolymers,ethylene vinyl acetate copolymers, maleic anhydride ester copolymers,branched polyethylenes, naphthalene, anthracene, microcrystalline waxand/or asphaltenes. Suitable dispersants include, but are not limitedto, dodecyl benzene sulfonate, oxyalkylated alkylphenols, andoxyalkylated alkylpnenolic resins. The paraffin crystal modifiers mayoptionally be combined with the dispersants.

d. Corrosion Inhibitors

Suitable corrosion inhibitors include, but are not limited to,amidoamines, quaternary amines, amides, and phosphate esters.

e. Scale Inhibitors

Suitable scale inhibitors include, but are not limited to, phosphates,phosphate esters, phosphoric acids, phosphonates, phosphonic acids,polyacrylamides, salts of acrylamido-methyl propane sulfonate/acrylicacid copolymer (AMPS/AA), phosphinated maleic copolymer (PHOS/MA), andsalts of a polymaleic acid/acrylic acid/acrylamido-methyl propanesulfonate terpolymer (PMA/AMPS).

f. Emulsifiers

Suitable emulsifiers include, but are not limited to, salts ofcarboxylic acids, products of acylation reactions between carboxylicacids or carboxylic anhydrides and amines, and alkyl, acyl and amidederivatives of saccharides (alkyl-saccharide emulsifiers).

g. Water Clarifiers

Suitable water clarifiers include, but are not limited to, inorganicmetal salts such as alum, aluminum chloride, and aluminum chlorohydrate,or organic polymers such as acrylic acid based polymers, acrylamidebased polymers, polymerized amines, alkanolamines, thiocarbamates, andcationic polymers such as diallyldimethylammonium chloride(DADMAC).

h. Dispersants

Suitable dispersants include, but are not limited to, aliphaticphosphonic acids with 2-50 carbons, such as hydroxyethyl diphosphonicacid, and aminoalkyl phosphonic acids, e.g. polyaminomethylenephosphonates with 2-10 N atoms e.g. each bearing at least one methylenephosphonic acid group; examples of the latter are ethylenediaminetetra(methylene phosphonate), diethylenetriamine penta(methylenephosphonate) and the triamine- and tetramine-polymethylene phosphonateswith 2-4 methylene groups between each N atom, at least 2 of the numbersof methylene groups in each phosphonate being different. Other suitabledispersion agents include lignin or derivatives of lignin such aslignosulfonate and naphthalene sulfonic acid and derivatives.

i. Emulsion Breakers

Suitable emulsion breakers include, but are not limited to,dodecylbenzylsulfonic acid (DDBSA), the sodium salt of xylenesulfonicacid (NAXSA), expoxlated and propoxylated compounds, anionic cationicand nonionic surfactants, and resins, such as phenolic and epoxideresins.

j. Hydrogen Sulfide Scavengers

Suitable hydrogen sulfide scavengers include, but are not limited to,oxidants (e.g., inorganic peroxides such as sodium peroxide, or chlorinedioxide), aldehydes (e.g., of 1-10 carbons such as formaldehyde orglutaraldehyde or (meth)acrolein), triazines (e.g., monoethanol aminetriazine, and monomethylamine triazine), and glyoxal.

k. Gas Hydrate Inhibitors

Suitable additional gas hydrate inhibitors include, but are not limitedto, thermodynamic hydrate inhibitors (THI), kinetic hydrate inhibitors(KHI), and anti-agglomerates (AA). Suitable thermodynamic hydrateinhibitors include, but are not limited to, NaCl salt, KCl salt, CaCl₂salt, MgCl₂ salt, NaBr₂ salt, formate brines (e.g. potassium formate),polyols (such as glucose, sucrose, fructose, maltose, lactose,gluconate, monoethylene glycol, diethylene glycol, triethylene glycol,mono-propylene glycol, dipropylene glycol, tripropylene glycols,tetrapropylene glycol, monobutylene glycol, dibutylene glycol,tributylene glycol, glycerol, diglycerol, triglycerol, and sugaralcohols (e.g. sorbitol, mannitol)), methanol, propanol, ethanol, glycolethers (such as diethyleneglycol monomethylether, ethyleneglycolmonobutylether), and alkyl or cyclic esters of alcohols (such as ethyllactate, butyl lactate, methylethyl benzoate). Suitable kinetic hydrateinhibitors and anti-agglomerates include, but are not limited to,polymers and copolymers, polysaccharides (such as hydroxy-ethylcellulose(HEC), carboxymethylcellulose (CMC), starch, starch derivatives, andxanthan), lactams (such as polyvinylcaprolactam, polyvinyl lactam),pyrrolidones (such as polyvinyl pyrrolidone of various molecularweights), surfactants (such as fatty acid salts, ethoxylated alcohols,propoxylated alcohols, sorbitan esters, ethoxylated sorbitan esters,polyglycerol esters of fatty acids, alkyl glucosides, alkylpolyglucosides, alkyl sulfates, alkyl sulfonates, alkyl estersulfonates, alkyl aromatic sulfonates, alkyl betaine, alkyl amidobetaines), hydrocarbon based dispersants (such as lignosulfonates,iminodisuccinates, polyaspartates), amino acids, and proteins.

l. Biocides

Suitable biocides include, but are not limited to, oxidizing andnon-oxidizing biocides. Suitable non-oxidizing biocides include, forexample, aldehydes (e.g., formaldehyde, glutaraldehyde, and acrolein),amine-type compounds (e.g., quaternary amine compounds and cocodiamine),halogenated compounds (e.g., bronopol and2-2-dibromo-3-nitrilopropionamide (DBNPA)), sulfur compounds (e.g.,isothiazolone, carbamates, and metronidazole), and quaternaryphosphonium salts (e.g., tetrakis(hydroxymethyl)phosphonium sulfate(THPS)). Suitable oxidizing biocides include, for example, sodiumhypochlorite, trichloroisocyanuric acids, dichloroisocyanuric acid,calcium hypochlorite, lithium hypochlorite, chlorinated hydantoins,stabilized sodium hypobromite, activated sodium bromide, brominatedhydantoins, chlorine dioxide, ozone, and peroxides.

m. pH Modifiers

Suitable pH modifiers include, but are not limited to, alkalihydroxides, alkali carbonates, alkali bicarbonates, alkaline earth metalhydroxides, alkaline earth metal carbonates, alkaline earth metalbicarbonates and mixtures or combinations thereof. Exemplary pHmodifiers include NaOH, KOH, Ca(OH)₂, CaO, Na₂CO₃, KHCO₃, K₂CO₃, NaHCO₃,MgO, and Mg(OH)₂.

n. Surfactants

Suitable surfactants include, but are not limited to, anionicsurfactants, cationic surfactants, and nonionic surfactants. Anionicsurfactants include alkyl aryl sulfonates, olefin sulfonates, paraffinsulfonates, alcohol sulfates, alcohol ether sulfates, alkyl carboxylatesand alkyl ether carboxylates, and alkyl and ethoxylated alkyl phosphateesters, and mono and dialkyl sulfosuccinates and sulfosuccinamates.Cationic surfactants include alkyl trimethyl quaternary ammonium salts,alkyl dimethyl benzyl quaternary ammonium salts, dialkyl dimethylquaternary ammonium salts, and imidazolinium salts. Nonionic surfactantsinclude alcohol alkoxylates, alkylphenol alkoxylates, block copolymersof ethylene, propylene and butylene oxides, alkyl dimethyl amine oxides,alkyl-bis(2-hydroxyethyl) amine oxides, alkyl amidopropyl dimethyl amineoxides, alkylamidopropyl-bis(2-hydroxyethyl) amine oxides, alkylpolyglucosides, polyalkoxylated glycerides, sorbitan esters andpolyalkoxylated sorbitan esters, and alkoyl polyethylene glycol estersand diesters. Also included are betaines and sultanes, amphotericsurfactants such as alkyl amphoacetates and amphodiacetates, alkylamphopropripionates and amphodipropionates, and alkyliminodiproprionate.

o. Solvents

Suitable solvents include, but are not limited to, water, isopropanol,methanol, ethanol, 2-ethylhexanol, heavy aromatic naphtha, toluene,ethylene glycol, ethylene glycol monobutyl ether (EGMBE), diethyleneglycol monoethyl ether, and xylene. Representative polar solventssuitable for formulation with the composition include water, brine,seawater, alcohols (including straight chain or branched aliphatic suchas methanol, ethanol, propanol, isopropanol, butanol, 2-ethylhexanol,hexanol, octanol, decanol, 2-butoxyethanol, etc.), glycols andderivatives (ethylene glycol, 1,2-propylene glycol, 1,3-propyleneglycol, ethylene glycol monobutyl ether, etc.), ketones (cyclohexanone,diisobutylketone), N-methylpyrrolidinone (NMP), N,N-dimethylformamideand the like. Representative of non-polar solvents suitable forformulation with the composition include aliphatics such as pentane,hexane, cyclohexane, methylcyclohexane, heptane, decane, dodecane,diesel, and the like; aromatics such as toluene, xylene, heavy aromaticnaphtha, fatty acid derivatives (acids, esters, amides), and the like.

In certain embodiments, the solvent is isopropanol, methanol, ethanol,heavy aromatic naptha, toluene, ethylene glycol, ethylene glycolmonobutyl ether (EGMBE), diethylene glycol monoethyl ether, xylene,kerosene, diesel, isobutanol, heptane, or a combination thereof.

In certain embodiments, a composition of the invention comprises from 0to about 80 percent by weight of one or more solvents, based on theweight of the composition. In certain embodiments, a composition of theinvention comprises from 0 to about 50 percent by weight of one or moresolvents, based on the weight of the composition. In certainembodiments, a composition of the invention comprises 20%, 25%, 30%,35%, 40%, 45%, or 50% by weight of one or more solvents, based on theweight of the composition.

p. Additional Components

Compositions made according to the invention may further includeadditional functional agents or additives that provide a beneficialproperty. Additional agents or additives will vary according to theparticular composition being manufactured and its intend use as oneskilled in the art will appreciate. According to one embodiment, thecompositions do not contain any of the additional agents or additives.

4. SYNTHETIC METHODS

The compounds and compositions of the invention can be better understoodin connection with the following synthetic schemes and methods whichillustrate a means by which the compounds can be prepared.

Compounds of formula (3) can be prepared as described in Scheme 1,wherein R¹, R³, R⁴, Z^(a), Z^(b), Z^(d), Z^(e), R^(a), R^(b), and m areas defined above; n is 2; and R¹⁰¹, R¹⁰², and R¹⁰³ are eachindependently selected from hydrogen, alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkyl, and heterocyclyl. Michael reaction between thecompound of formula (1) and the compound of formula (2) will providecompounds of formula (3). The reaction may optionally be conducted neator in one or more solvents, and optionally at elevated temperature(e.g., 80° C.-90° C.). Various protecting groups (e.g., esters, ethers,acetals, amides) may be used as necessary to mask other reactivefunctional groups that may be present in the compounds of formula (1)and formula (2).

In certain embodiments, R¹⁰¹, R¹⁰², and R¹⁰³ are each independentlyselected from hydrogen and alkyl. In certain embodiments, R¹⁰¹, R¹⁰²,and R¹⁰³ are each independently selected from hydrogen and C₁-C₆ alkyl.In certain embodiments, R¹⁰¹, R¹⁰², and R¹⁰³ are each independentlyhydrogen.

In certain embodiments, Z^(a) is C(R⁵R⁶); Z^(b) is C(R⁸R⁹); Z^(d) isC(R¹²R¹³); and Z^(e) is C(R¹⁵R¹⁶), wherein R⁵, R⁶, R⁸, R⁹, R¹², R¹³,R¹⁵, and R¹⁶ are as defined above. In certain embodiments, Z^(a) isC(R⁵R⁶); Z^(b) is C(R⁸R⁹); Z^(d) is C(R¹²R¹³); and Z^(e) is C(R¹⁵R¹⁶),wherein R⁵, R⁶, R⁸, R⁹, R¹², R¹³, R¹⁵, and R¹⁶ are each a hydrogen atom.

In certain embodiments, R¹⁰¹, R¹⁰² and R¹⁰³ are each independentlyselected from hydrogen and alkyl; Z^(a) is C(R⁵R⁶) Z^(b) is C(R⁸R⁹)Z^(d) is C(R¹²R¹³), and Z^(e) is C(R¹⁵R¹⁶), wherein R⁵, R⁶, R⁸, R⁹, R¹²,R¹³, R¹⁵, and R¹⁶ are each a hydrogen atom; R¹ is alkyl or alkenyl; R³is hydrogen or alkyl; and R⁴ is alkyl. In certain embodiments, R¹⁰¹,R¹⁰², and R¹⁰³ are each independently selected from hydrogen and C₁-C₆alkyl; Z^(a) is C(R⁵R⁶), Z^(b) is C(R⁸R⁹) Z^(d) is C(R¹²R¹³), and Z^(e)is C)R¹⁵R¹⁶), wherein R⁵, R⁶, R⁸, R⁹, R¹², R¹³, R¹⁵, and R¹⁶ are eachindependently a hydrogen atom; R¹ is C₁-C₂₂ alkyl or C₂-C₂₂ alkenyl; R³is hydrogen or methyl; and R⁴ is methyl. In certain embodiments, R¹⁰¹,R¹⁰², and R¹⁰³, are each independently selected from hydrogen; Z^(a) isC(R⁵R⁶), Z^(b) is C(R⁸R⁹), Z^(d) is C(R¹²R¹³), and Z^(e) is C(R¹⁵R¹⁶),wherein R⁵, R⁶, R⁸, R⁹, R¹², R¹³, R¹⁵, and R¹⁶ are each independently ahydrogen atom; R¹ is —C₁₂H₂₅, —C₁₈H₃₇, or —C₁₈H₃₅; R³ is hydrogen; andR⁴ is methyl.

Compounds of formula (6) can be prepared as described in Scheme 2,wherein R¹, R³, R⁴, Z^(a), Z^(b), Z^(c), Z^(d), Z^(e), R^(a), R^(b), m,and n are as defined above; and R²⁰¹ and R²⁰³ are functional groups thatmay undergo coupling reactions known in the art. For example, in certainembodiments, R²⁰¹ and R²⁰³ may be include alkenyl groups (e.g., terminalalkene groups) that can undergo cross-metathesis via an appropriategeneration Grubbs or Schrock catalyst; followed by hydrogenation toprovide the —(CR^(a)R^(b))_(n)— group of the compound of formula (6).Alternatively, R²⁰¹ and R²⁰³ may include functional groups amenable toknown metal-catalyzed coupling reactions (e.g., Heck reaction, Stillecoupling, etc.). Various protecting groups may be used as necessary tomask other reactive functional groups that may be present in thecompounds of formula (4) and formula (5).

Compounds of formula (8) or compounds of formula (9) can be prepared asdescribed in Scheme 3, wherein R¹, R², R³, R⁴, Z^(a), Z^(b), Z^(c),Z^(d), Z^(e), R^(a), R^(b), X⁻, m, and n are as defined above, providedthat R² and X⁻ are both present. Treatment of compounds of formula (3)or formula (6) with an electrophile of formula R²—X will providecompounds of formula (8) or formula (9), wherein R² of R²—X is asdefined above, and X of R²—X is a suitable leaving group or counterion(e.g., tosylate, mesylate, halogen). The reaction may be conducted underelevated temperature (e.g., reflux temperature) and optionally in thepresence of one or more solvents (e.g., isopropanol).

Compounds of formula (2) can be prepared as described in Scheme 4,wherein R¹, R³, R¹⁰¹, R¹⁰², R¹⁰³, and m are as defined above. Treatmentof a compound of formula (10), such as acrylic acid, with an alcohol offormula (11), such as an ethoxylated fatty alcohol, will providecompounds of formula (2) via acid catalyzed esterification. The reactionmay be conducted at elevated temperature (e.g., reflux temperature, suchas 90° C.), and optionally in the presence of a solvent (e.g.,cyclohexane). An acid catalyst (e.g., p-toluenesulfonic acid) may beused to drive the reaction forth, as well as distillation of waterby-product formed upon ester formation.

Compounds of formula (1), formula (4), and formula (5) may becommercially available, or may optionally be prepared using syntheticmethodologies known to those skilled in the art.

In certain embodiments, the beta-amino ester surfactants may be furthermodified, for example, by manipulation of substituents. Thesemanipulations may include, but are not limited to, reduction, oxidation,organometallic cross-coupling, alkylation, acylation, and hydrolysisreactions which are commonly known to those skilled in the art. In somecases, the order of carrying out the foregoing reaction schemes may bevaried to facilitate the reaction or to avoid unwanted reactionproducts.

5. PRODUCT BY PROCESS

The compounds and compositions of the invention include compounds andcompositions produced by a process comprising reaction, preferablyMichael reaction, between a compound of formula (1) and a compound offormula (2), as described above. The compounds and compositions of theinvention also include compounds and compositions produced by a processcomprising reacting a compound of formula (4) with a compound of formula(5), with for example, cross-metathesis via an appropriate generationGrubbs or Schrock catalyst, followed by hydrogenation.

The products produced by the processes disclosed herein may be usedneat, or prepared as compositions comprising one or more additives asdescribed herein. The products may be used in methods of inhibitingformation of gas hydrate agglomerates, as described herein.

6. METHODS OF USE

The compounds and compositions of the invention may be used forinhibiting the formation of gas hydrate agglomerates. The compounds andcompositions may be used to inhibit formation of gas hydrates in a fluidcomprising water, gas, and optionally liquid hydrocarbon, by treatingsaid fluid with an effective amount of a compound or composition of theinvention, as described herein. The compounds and compositions of theinvention can be used in any industry where it is desirable to inhibitgas hydrate agglomerates. In certain embodiments, the compounds andcompositions can be applied to a gas or liquid produced or used in theproduction, transportation, storage, and/or separation of crude oil ornatural gas.

The compounds and compositions may be added to any fluid susceptible toforming gas hydrates. A fluid to which the compounds and compositionsmay be introduced may be an aqueous medium. The aqueous medium maycomprise water, gas, and optionally liquid hydrocarbon. A fluid to whichthe compounds and compositions may be introduced may be a liquidhydrocarbon. The liquid hydrocarbon may be any type of liquidhydrocarbon including, but not limited to, crude oil, heavy oil,processed residual oil, bitminous oil, coker oils, coker gas oils, fluidcatalytic cracker feeds, gas oil, naphtha, fluid catalytic crackingslurry, diesel fuel, fuel oil, jet fuel, gasoline, and kerosene. Incertain embodiments, the fluid or gas may be a refined hydrocarbonproduct. In certain embodiments, the fluid or gas may be a crude oilproduct.

A fluid or gas treated with a compound or composition of the inventionmay be at any selected temperature. A fluid or gas treated with acompound or composition of the invention may be at any selectedpressure.

The compounds and compositions of the invention may be added to a fluidhaving various levels of water cut. For example, the water cut may befrom 0% to 100% volume/volume (v/v), from 1% to 80% v/v, from 1% to 70%v/v, from 1% to 65% v/v, from 1% to 60% v/v, from 10% to 80% v/v, from20% to 70% v/v, or from 40% to 65% v/v. The water cut may be 1% v/v, 2%v/v, 3% v/v, 4% v/v, 5% v/v, 6% v/v, 7% v/v, 8% v/v, 9% v/v, 10% v/v,11% v/v, 12% v/v, 13% v/v, 14% v/v, 15% v/v, 16% v/v, 17% v/v, 18% v/v,19% v/v, 20% v/v, 21% v/v, 22% v/v, 23% v/v, 24% v/v, 25% v/v, 26% v/v,27% v/v, 28% v/v, 29% v/v, 30% v/v, 31% v/v, 32% v/v, 33% v/v, 34% v/v,35% v/v, 36% v/v, 37% v/v, 38% v/v, 39% v/v, 40% v/v, 41% v/v, 42% v/v,43% v/v, 44% v/v, 45% v/v, 46% v/v, 47% v/v, 48% v/v, 49% v/v, 50% v/v,51% v/v, 52% v/v, 53% v/v, 54% v/v, 55% v/v, 56% v/v, 57% v/v, 58% v/v,59% v/v, 60% v/v, 61% v/v, 62% v/v, 63% v/v, 64% v/v, 65% v/v, 66% v/v,67% v/v, 68% v/v, 69% v/v, 70% v/v, 71% v/v, 72% v/v, 73% v/v, 74% v/v,75% v/v, 76% v/v, 77% v/v, 78% v/v, 79% v/v, 80% v/v, 81% v/v, 82% v/v,83% v/v, 84% v/v, 85% v/v, 86% v/v, 87% v/v, 88% v/v, 89% v/v, 90% v/v,91% v/v, 92% v/v, 93% v/v, 94% v/v, 95% v/v, 96% v/v, 97% v/v, 98% v/v,99% v/v, or 100% v/v.

The compounds and compositions of the invention may be added to a fluidhaving various levels of salinity. In one embodiment, the fluid may havea salinity of 0% to 25%, about 1% to 24%, 1% to 20%, or about 10% to 25%weight/weight (w/w) total dissolved solids (TDS).

The fluid or gas in which the compounds and compositions of theinvention are introduced may be contained in and/or exposed to manydifferent types of apparatuses. For example, the fluid or gas may becontained in an apparatus that transports fluid or gas from one point toanother, such as an oil and/or gas pipeline. In certain embodiments, theapparatus may be part of an oil and/or gas refinery, such as a pipeline,a separation vessel, a dehydration unit, or a gas line. The fluid may becontained in and/or exposed to an apparatus used in oil extractionand/or production, such as a wellhead. The apparatus may be a cargovessel, a storage vessel, or a holding tank. In certain embodiments, thefluid or gas may be contained in water systems, condensate/oilsystems/gas systems, or any combination thereof.

The compounds or compositions of the invention may be introduced into afluid or gas by any appropriate method for ensuring dispersal of theinhibitor through the fluid or gas. The compounds and compositions maybe injected using mechanical equipment such as chemical injection pumps,piping tees, injection fittings, and the like. The compounds andcompositions of the invention may be introduced with or without one ormore additional polar or non-polar solvents depending upon theapplication and requirements. In certain embodiments, the compounds andcompositions of the invention may be pumped into an oil and/or gaspipeline using an umbilical line. In certain embodiments, capillaryinjection systems can be used to deliver the compounds and compositionsto a selected fluid. In certain embodiments, the compounds andcompositions can be injected into a gas or liquid as an aqueous ornonaqueous solution, mixture, or slurry.

The compounds and compositions of the invention may be added to a fluidor gas in any amount sufficient to inhibit formation of gas hydrateagglomerates. In certain embodiments, the compounds and compositions ofthe invention may be applied to a fluid (e.g., a fluid contained in anoil and/or gas pipeline, well, or other apparatus) in a dose of about0.1% volume to about 2% volume based on water cut.

The compounds and compositions may be applied to a fluid or gas at toprovide any desired inhibitor concentration. Each system may have itsown requirements, and may require a higher or lower dose rate of acompound or composition of the invention.

The compounds, compositions, methods, and processes of the inventionwill be better understood by reference to the following examples, whichare intended as an illustration of and not a limitation upon the scopeof the invention.

7. EXAMPLES

The foregoing may be better understood by reference to the followingexamples, which are presented for purposes of illustration and are notintended to limit the scope of the invention.

a. Intermediates

Intermediate 1 3,6,9,12-tetraoxatetracosyl acrylate

50.0 g (0.14 mole) of Brij 30 (3,6,9,12-tetraoxatetracosan-1-ol),purchased from Sigma-Aldrich, St. Louis, MO, is charged into a 250 mLround bottom flask equipped with a distillation trap, condenser,thermocouple, and magnetic stirrer. Then, cyclohexane (40 g) andp-toluenesulfonic acid (5.2 g, 0.03 mole) are added to the reaction andthe mixture is agitated using the magnetic stirrer. The temperature isadjusted to reflux (˜90° C.) for 2 hours to distill any water present inthe reaction mass. Acrylic acid (15.0 g, 0.21 mole) is then injectedinto the reactor while maintaining the reflux conditions. Water beginsto distill from the reaction mass indicating the esterification reactionis proceeding as anticipated. The reaction is allowed to continueovernight and 3.3 g of water are distilled. The resulting productsolution is extracted with 100 mL of saturated sodium bicarbonate toneutralize the excess acid on the reaction mass. The organic phase isseparated and the solvent removed to obtain 57.4 g (0.14 mole) ofproduct. The final product is a light yellow solid at ambienttemperature. An 80% to 90% conversion of the alcohol to acrylate esteris estimated from the integration area of the olefin protons on the NMRspectra and comparing them against the methyl group from the hydrocarbontail. ¹H-NMR (300 MHz, CDCl₃): δ 6.05 (m, 1H), 5.83 (m, 1H), 5.51 (d,9.0 Hz, 2H), 3.96 (m, 2H), 3.28 (m, 12H), 3.11 (t, 6.6 Hz, 2H), 1.25 (m,2H), 0.98 (m, 18H), 0.56 (t, 4.4 Hz, 3H). ¹³C-NMR (75 MHz, CDCl₃): δ164.60, 129.58, 129.13, 127.82, 127.56, 70.42, 70.38, 69.71, 69.26,68.14, 63.42, 62.63, 31.05, 28.82, 28.78, 28.65, 28.50, 28.41, 27.79,25.28, 25.07, 21.78, 13.16.

Intermediate 2 (Z)-2-(2-(octadec-9-enyloxy)ethoxy)ethyl acrylate

Intermediate 2 is prepared by synthetic methods described herein.

Intermediate 3 3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracontylacrylate

Intermediate 3 is prepared by synthetic methods described herein.

Intermediate 43,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacontylacrylate

Intermediate 4 is prepared by synthetic methods described herein.

Intermediate 5(Z)-3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracont-39-enyl acrylate

Intermediate 5 is prepared by synthetic methods described herein.

Intermediate 6(Z)-3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacont-69-enylacrylate

Intermediate 6 is prepared by synthetic methods described herein.

b. Beta-Amino Ester Surfactants

Example 1 3,6,9,12-tetraoxatetracosyl3-(4-methylpiperazin-1-yl)propanoate R¹ is —C₁₂H₂₅; R² is absent; R³ isH; X⁻ is absent; m is 4

In a 250 mL round bottom flask, 26.3 g (0.063 mole) of3,6,9,12-tetraoxatetracosyl acrylate and 6.3 g (0.063 mole) of1-methylpiperazine are combined and agitated with a magnetic stirrerbar. The temperature is then adjusted to 85° C. and the reaction isallowed to continue overnight. The resulting product is obtained in 96%yield as a light brown liquid at ambient temperature.

Example 21-butyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide R¹ is —C₁₂H₂₅; R² is —C₄H₉; R³ is H; X⁻ is Br⁻; m is 4

The product of Example 2 is prepared by synthetic methods describedherein.

Example 31-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide R¹ is —C₁₂H₂₅; R² is —C₆H₁₃; R³ is H; X⁻ is Br⁻; m is 4

In a 100 mL round bottom flask, 10.0 g (0.019 mole) of3,6,9,12-tetraoxatetracosyl 3-(4-methylpiperazin-1-yl)propanoate and 3.2g (0.019 mole) of 1-bromohexane are combined with 3.3 g of isopropylalcohol. This solution is heated to reflux overnight. After the reactionis completed, 16.5 g of methanol are added to obtain a solution with 40%active ingredient. The resulting formulation of the product is a darkbrown liquid at ambient temperature. ¹H-NMR (300 MHz, CDCl₃): δ 3.68 (m,2H), 3.09 (m, 21H), 2.86 (m, 4H), 2.38 (m, 4H), 2.19 (m, 2H), 2.00 (m,2H), 1.02 (m, 2H), 0.73 (m, 26H), 0.36 (m, 6H). ¹³C-NMR (75 MHz, CDCl₃):δ 170.50, 70.00, 69.20, 68.75, 67.69, 62.33, 62.23, 61.95, 58.91, 53.15,51.82, 51.05, 50.32, 45.80, 45.04, 43.77, 31.06, 30.94, 30.54, 29.94,28.34, 28.28, 28.25, 28.12, 27.96, 27.32, 24.77, 24.69, 24.59, 24.15,21.28, 21.08, 20.63, 12.74, 12.62.

Example 4 (Z)-2-(2-(octadec-9-enyloxy)ethoxy)ethyl3-(4-methylpiperazin-1-yl)propanoate R¹ is —C₁₈H₃₅; R² is absent; R³ isH; X⁻ is absent; m is 2

The product of Example 4 is prepared by synthetic methods describedherein.

Example 5(Z)-1-butyl-1-methyl-4-(3-(2-(2-(octadec-9-enyloxy)ethoxy)ethoxy)-3-oxopropyl)piperazin-1-iumbromide R¹ is —C₁₈H₃₅; R² is —C₄H₉; R³ is H; X⁻ is Br⁻; m is 2

The product of Example 5 is prepared by synthetic methods describedherein.

Example 6(Z)-1-hexyl-1-methyl-4-(3-(2-(2-(octadec-9-enyloxy)ethoxy)ethoxy)-3-oxopropyl)piperazin-1-iumbromide R¹ is —C₁₈H₃₅; R² is —C₆H₁₃; R³ is H; X⁻ is Br⁻; m is 2

The product of Example 6 is prepared by synthetic methods describedherein.

Example 7 3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracontyl3-(4-methylpiperazin-1-yl)propanoate R¹ is —C₁₈H₃₇; R² is absent; R³ isH; X⁻ is absent; m is 10

The product of Example 7 is prepared by synthetic methods describedherein.

Example 81-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacontyppiperazin-1-iumbromide R¹ is —C₁₈H₃₇; R² is —C₄H₉; R³ is H; X⁻ is Br⁻; m is 10

The product of Example 8 is prepared by synthetic methods describedherein.

Example 91-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacontyl)piperazin-1-iumbromide R¹ is —C₁₈H₃₇; R² is —C₆14₁₃; R³ is H; X⁻ is Br⁻; m is 10

The product of Example 9 is prepared by synthetic methods describedherein.

Example 103,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacontyl3-(4-methylpiperazin-1-yl)propanoate R¹ is —C₁₈H₃₇; R² is absent; R³ isH; X⁻ is absent; m is 20

The product of Example 10 is prepared by synthetic methods describedherein.

Example 111-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacontyppiperazin-1-iumbromide R¹ is —C₁₈H₃₇; R² is —C₄H₉; R³ is H; X⁻ is Br⁻, m is 20

The product of Example 11 is prepared by synthetic methods describedherein.

Example 121-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacontyppiperazin-1-iumbromide R¹ is —C₁₈H₃₇; R² is —C₆H₁₃; R³ is H; X⁻ is Br⁻, m is 20

The product of Example 12 is prepared by synthetic methods describedherein.

Example 13(Z)-3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracont-39-enyl3-(4-methylpiperazin-1-yl)propanoateR¹ is —C₁₈H₃₅; R² is absent; R³ is H; X⁻ is absent; m is 10

The product of Example 13 is prepared by synthetic methods describedherein.

Example 14(Z)-1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacont-43-enyl)piperazin-1-iumbromide R¹ is —C₁₈H₃₅; R² is —C₄H₉; R³ is H; X⁻ is Br⁻; m is 10

The product of Example 14 is prepared by synthetic methods describedherein.

Example 15(Z)-1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacont-43-enyl)piperazin-1-iumbromide R¹ is —C₁₈H₃₅; R² is —C₆H₁₃; R³ is H; X⁻ is Br⁻, m is 10

The product of Example 15 is prepared by synthetic methods describedherein.

Example 16(Z)-3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacont-69-enyl3-(4-methylpiperazin-1-yl)propanoateR¹ is —C₁₈H₃₅; R² is absent; R³ is H; X⁻ is absent; m is 20

The product of Example 16 is prepared by synthetic methods describedherein.

Example 17(Z)-1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacont-73-enyl)piperazin-1-iumbromide (R¹ is —C₁₈H₃₅; R² is —C₄H₉; R³ is H; X⁻ is Br⁻, m is 20

The product of Example 17 is prepared by synthetic methods describedherein.

Example 18(Z)-1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacont-73-enyl)piperazin-1-iumbromide R¹ is —C₁₈H₃₅; R² is —C₆H₁₃; R³ is H; X⁻ is Br⁻, m is 20

The product of Example 18 is prepared by synthetic methods describedherein.

c. Anti-Agglomeration Performance

The anti-agglomeration performance for all the Examples is conductedusing the Rocking Cell testing method. A Rocking Cell has two parts, amanifold and a cell body. The manifold is made up of stainless steelfittings that are welded together. It has three stems. An inlet stem isused to charge gas into the cell. An outlet stem is used to release thegas out of the cell. The third stem connects to a transducer, whichmeasures the pressure inside of the cell. The cell body has threelayers. The outer layer is a polycarbonate tube, with a thickness thatis 0.7 cm. The middle layer is made of a stainless steel metal and isconnected to the manifold. The inner layer contains a high-pressuresapphire tube, which has an outer diameter that is 2.8 cm, an innerdiameter that is 1.85 cm, and a length that is 5 cm. This sapphire tubecan handle up to 3000 psi. A stainless steel ball, which has a 1.6 cmdiameter, is located inside a sapphire tube to induce turbulence and mixthe fluids during the rocking process.

The test fluid usually contains three different components. For theAnti-Agglomerant test, 7.2 mL of warm magnolia crude oil is firstinjected into the cell. Next, 4.8 mL of a solution containing 7% byweight based upon actives of NaCl and deionized (DI) water is injectedinto the cell to make a 40% water cut mixture. AA chemicals are theninjected into the cell. The dosage of the AA chemical is based on theamount of aqueous phase. The initial condition for the test had atemperature of 21° C. Each cell is charged by Green Canyon gas andpressurized up to 2500 psi. The cells are rocked for at least 1.5 to 2hours until the fluid is saturated and the pressure becomes stable; thenthe temperature is set at 4° C. The rocking sequence is the following:cells are rocked for 16 hours (simulating steady state flowing);maintained static for 6 hours; and then rocked back for 2 hours.Pressure data is recorded during this time. Observations are taken everytwo or three hours before the rocking is stopped and right after thestart up of the rocking test.

The AAs exemplified above are diluted in methanol (e.g., to a finalconcentration of 40% or 60% actives). The solutions are then dosed toobtain a final concentration of 1.5% volume of AA (based upon actives)in the aqueous phase. The mixture is charged into the rocking cell, asdescribed above, and a stainless steel ball is added to promote mixingduring the rocking part of the experiment

Table 1 shows that the performance of a hydrate inhibitor is ranked from1 (the worst performer) to 5 (the best) based on the following criteria:

TABLE 1 Low Dose Hydrate Inhibitor (LDHI) Rating System Rat- Test ingresult Observations 1 Fail The rolling ball is stuck and/or the liquidlevel has dropped below an observable amount. 2 Fail Large to mediumagglomerates are present and/or the liquid level has droppedsignificantly. There is significant resistance to the rolling of theball in the cell. 3 Marginal Medium agglomerates are formed in theviewable area pass and/or the liquid level has dropped moderately. Thereis some resistance to the rolling ball in the cell. 4 Pass Smallagglomerates are formed and/or the liquid level has dropped slightly,but the solution is free flowing without hindrance. 5 Pass Tiny andwell-dispersed hydrates in the hydrocarbon phase, high liquid level, andfree-flowing without hinderance.

The testing conditions are the same for all the Examples with theexemption of increasing water cuts to determine the maximum amount ofwater that each chemical could tolerate. Only the examples that providedgood anti-agglomeration effect at the lowest water cut of 20% or higherare described below. However, failure under the tested conditions doesnot necessarily indicate that the chemicals are not effective AAsbecause they may be able to perform under slightly different testingconditions.

Table 2 shows the results obtained from multiple Rocking Cellexperiments at increasing water cuts using1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide (Example 2) as the gas hydrate inhibitor. At 40% water cut, 100%of the experiments passed the test of preventing agglomeration of gashydrates. At water cuts greater than 40%, Example 2 is not effective asan anti-agglomerate chemical for the inhibition of gas hydrates.

TABLE 2 Inhibition of gas hydrate agglomeration by Example 2 Number ofNumber of Percentage Water Cut Dose Tests Passes of Passes 40% 1.5% 2 2100% 45% 1.5% 1 0 0% 50% 1.5% 1 0 0% 60% 1.5% 1 0 0%

Table 3 presents the Rocking Cell results for1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide (Example 3) at water cuts ranging from 40% to 60%. This chemicaldemonstrates anti-agglomeration performance at water cuts ranging from40% to 55%.

TABLE 3 Inhibition of gas hydrate agglomeration by Example 3 Number ofNumber of Percentage of Water Cut Dose Tests Passes Passes 40% 1.5% 2 2100% 45% 1.5% 1 1 100% 50% 1.5% 1 1 100% 55% 1.5% 1 1 100% 60% 1.5% 1 00%

Table 4 presents the Rocking Cell results for(Z)-1-hexyl-1-methyl-4-(3-(2-(2-(octadec-9-enyloxy)ethoxy)ethoxy)-3-oxopropyl)piperazin-1-iumbromide (Example 6) at water cuts ranging from 40% to 70%. Example 6 iscapable of preventing the agglomeration of gas hydrates at water cuts upto 65%. This chemical does not prevent agglomeration of hydrates at 70%water cut in the Rocking Cell test.

TABLE 4 Inhibition of gas hydrate agglomeration by Example 6 Number ofNumber of Percentage of Water Cut Dose Tests Passes Passes 40% 1.5% 2 2100% 45% 1.5% 1 1 100% 50% 1.5% 1 1 100% 55% 1.5% 1 1 100% 60% 1.5% 1 1100% 65% 1.5% 1 1 100% 70% 1.5% 1 0 0%

Accordingly, compounds and compositions of the invention are effectiveanti-agglomerates. The compounds and compositions are particularlyeffective anti-agglomerates at high water (e.g., above 40%), asdemonstrated by the performance of Examples 3 and 6.

Any ranges given either in absolute terms or in approximate terms areintended to encompass both, and any definitions used herein are intendedto be clarifying and not limiting. Notwithstanding that the numericalranges and parameters setting forth the broad scope of the invention areapproximations, the numerical values set forth in the specific examplesare reported as precisely as possible. Any numerical value, however,inherently contains certain errors necessarily resulting from thestandard deviation found in their respective testing measurements.Moreover, all ranges disclosed herein are to be understood to encompassany and all subranges (including all fractional and whole values)subsumed therein.

Furthermore, the invention encompasses any and all possible combinationsof some or all of the various embodiments described herein. Any and allpatents, patent applications, scientific papers, and other referencescited in this application, as well as any references cited therein, arehereby incorporated by reference in their entirety.

1. A compound of formula (I),

wherein R¹ is unsubstitued alkyl, or unsubstituted alkenyl; R² ishydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, or heterocyclyl, or R²may be absent; R³ is hydrogen or alkyl; R⁴ is unsubstitued alkyl, orunsubstitued alkenyl; Z^(a) is C(R⁵R⁶), O, S, or N(R⁷); Z^(b) isC(R⁸R⁹), O, S, or)N(R¹⁰); Z^(c) is C(R¹¹) or N; Z^(d) is C(R¹²R¹³), O,S, or N(R¹⁴); Z^(e) is C(R¹⁵R¹⁶), O, S, or N(R¹⁷); R⁵, R⁶, R⁷, R⁸, R⁹,R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, and R¹⁷ are each independentlyselected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl,aryl, heteroaryl, cycloalkyl, and heterocyclyl; R^(a) is independentlyselected from, at each occurrence, the group consisting of hydrogen,alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, and heterocyclyl;R^(b) is independently selected from, at each occurrence, the groupconsisting of hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkyl, and heterocyclyl; X⁻ is a counterion or X⁻ may be absent,provided that X⁻ is present when R² is present and X⁻ is absent when R²is absent; m is any one of an integer from 1 to 100; and n is any one ofan integer from 1 to 50; wherein unless otherwise designated said alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, and heterocyclyl areeach independently, at each occurrence, substituted or unsubstitutedwith a suitable substituent.
 2. The compound of claim 1, wherein R¹ isunsubstituted C₁-C₂₂ alkyl or unsubstituted C₂-C₂₂ alkenyl; R² isabsent; R³ is hydrogen or unsubstituted C₁-C₆ alkyl; R⁴ is unsubstitutedC₁-C₆ alkyl; Z^(a) is C(R⁵R⁶); Z^(b) is C(R⁸R⁹); Z^(c) is N; Z^(d) isC(R¹²R¹³); Z^(e) is C(R¹⁵R¹⁶); R⁵, R⁶, R⁸, R⁹, R¹², R¹³, R¹⁵, and R¹⁶are each independently selected from the group consisting of hydrogenand unsubstituted C₁-C₆ alkyl; R^(a) is hydrogen at each occurrence;R^(b) is hydrogen at each occurrence; X⁻ is absent; m is any one of aninteger from 1 to 20; and n is
 2. 3. The compound of claim 1, wherein R¹is unsubstituted C₁-C₂₂ alkyl or unsubstituted C₂-C₂₂ alkenyl; R² isunsubstituted C₁-C₁₀ alkyl; R³ is hydrogen or unsubstituted C₁-C₆ alkyl;R⁴ is unsubstituted C₁-C₆ alkyl; Z^(a) is C(R⁵R⁶); Z^(b) is C(R⁸R⁹);Z^(c) is N; Z^(d) is C(R¹²R¹³); Z^(e) is C(R¹⁵R¹⁶); R⁵, R⁶, R⁸, R⁹, R¹²,R¹³, R¹⁵, and R¹⁶ are each independently selected from the groupconsisting of hydrogen and unsubstituted C₁-C₆ alkyl; R^(a) is hydrogenat each occurrence; R^(b) is hydrogen at each occurrence; X⁻ is bromideor chloride; m is any one of an integer from 1 to 20; and n is
 2. 4. Thecompound of claim 1, wherein R³ is hydrogen.
 5. The compound of claim 1,wherein R⁵, R⁶, R⁸, R⁹, R¹², R¹³, R¹⁵, and R¹⁶ are each hydrogen.
 6. Thecompound of claim 1, wherein m is 2, 4, 10, or
 20. 7. The compound ofclaim 1, wherein R¹ is —C₁₂H₂₅, —C₁₈H₃₇, or —C₁₈H₃₅.
 8. The compound ofclaim 1, having the formula (V),


9. The compound of claim 8, wherein R¹ is —(CH₂)₁₁CH₃, —(CH₂)₁₇CH₃, or—(CH₂)₈CH═CH(CH₂)₇CH₃; R² is —(CH₂)₃CH₃, —(CH₂)₅CH₃, or R² is absent;and X⁻ is bromide, or X⁻ is absent, provided that X⁻ is present when R²is present and X⁻ is absent when R² is absent.
 10. The compound of claim9, wherein m is 2, 4, 10, or
 20. 11. The compound of claim 10, selectedfrom the group consisting of:3,6,9,12-tetraoxatetracosyl3-(4-methylpiperazin-1-yl)propanoate;1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide;1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16-pentaoxaoctacosyl)piperazin-1-iumbromide; (Z)-2-(2-(octadec-9-enyloxy)ethoxy)ethyl3-(4-methylpiperazin-1-yl)propanoate;(Z)-1-butyl-1-methyl-4-(3-(2-(2-(octadec-9-enyloxy)ethoxy)ethoxy)-3-oxopropyl)piperazin-1-iumbromide;(Z)-1-hexyl-1-methyl-4-(3-(2-(2-(octadec-9-enyloxy)ethoxy)ethoxy)-3-oxopropyl)piperazin-1-iumbromide; 3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracontyl3-(4-methylpiperazin-1-yl)propanoate;1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacontyl)piperazin-1-iumbromide;1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacontyl)piperazin-1-iumbromide;3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacontyl3-(4-methylpiperazin-1-yl)propanoate;1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacontyl)piperazin-1-iumbromide; 1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacontyl)piperazin-1-iumbromide; (Z)-3,6,9,12,15,18,21,24,27,30-decaoxaoctatetracont-39-enyl3-(4-methylpiperazin-1-yl)propanoate;(Z)-1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacont-43-enyl)piperazin-1-iumbromide;(Z)-1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34-undecaoxadopentacont-43-enyl)piperazin-1-iumbromide;(Z)-3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-icosaoxaoctaheptacont-69-enyl3-(4-methylpiperazin-1-yl)propanoate;(Z)-1-butyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacont-73-enyl)piperazin-1-iumbromide; and(Z)-1-hexyl-1-methyl-4-(3-oxo-4,7,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64-henicosaoxadooctacont-73-enyl)piperazin-1-iumbromide.
 12. A composition comprising a mixture of compounds of formula(I) according to claim
 8. 13. The composition of claim 12, furthercomprising one or more additives independently selected from the groupconsisting of a synergistic compound, an asphaltene inhibitor, aparaffin inhibitor, a corrosion inhibitor, a scale inhibitor, anemulsifier, a water clarifier, a dispersant, an emulsion breaker, ahydrogen sulfide scavenger, a gas hydrate inhibitor, a biocide, a pHmodifier, a surfactant, and a solvent.
 14. The composition of claim 13,comprising at least one solvent.
 15. The composition of claim 14,wherein the solvent is isopropanol, methanol, ethanol, heavy aromaticnaptha, toluene, ethylene glycol, ethylene glycol monobutyl ether(EGMBE), diethylene glycol monoethyl ether, xylene, kerosene, diesel,isobutanol, heptane, or a combination thereof.
 16. A method ofinhibiting the formation of hydrate agglomerates in a fluid comprisingwater, gas, and optionally liquid hydrocarbon, the method comprisingadding to the fluid an effective amount of a composition comprising oneor more compounds of formula (I) according to claim
 1. 17. The method ofclaim 16, wherein said fluid has a salinity of 1 to 20 w/w percent totaldissolved solids (TDS).
 18. The method of claim 16, wherein said fluidhas a water cut from 1 to 65 v/v percent.
 19. The method of claim 16,wherein the fluid is contained in an oil or gas pipeline.